So first Laidlaw puts forth the argument that getting action gamers into RPG is a matter of interface - they don't want to see the die rolls, don't want to see the numbers, they don't want to think about it. That's fine, that's good for them. If it's an issue of how you're presenting information, then there's a very easy way around this problem: you simply reduce the UI elements, add pre-rolled characters and offer auto-leveling schemes that work for your game... oh, right, you already did all those things in previous games! Maybe the problem wasn't the game itself, then, but how you offered those options to players, hm?
Then, Laidlaw seems to backtrack and say it's a matter of game mechanics - that they tried to play with them in Dragon Age II and are trying to find a middle ground between Origins and the sequel, but ended up failing in Dragon Age II. The goal, in his words, is to offer complexity and depth, and I think Origins did a pretty good job of that despite its flaws; reducing the complexity of the game systems in Dragon Age II did nothing but damage combat and turn it into a boring grind. Its problem was just that - lack of depth and complexity.
Why is BioWare attempting to build RPGs for a mass market, for action fans, anyway? Here's a hint: if someone doesn't like RPGs, trying to hide the fact they're playing an RPG from them won't make them like your game any more; it won't trick them into thinking they're playing an action title; all it will do is damage your game for people who do actually like RPGs. You can find a middle ground, but you can't do it without compromising mechanics or the experience of players in some way... you can do a good job of hiding the stats, but sooner or later the player is going to run into them, just as offering a "casual mode" versus "hardcore mode" (or whatever) will split your fanbase in two and give both sides something to complain about. No matter how good a job you do, someone's going to be upset for some reason or your game is going to suffer for it in some way... but since Laidlaw seems so set on doing it anyway, I'll ignore that problem for now.
What it really comes down to is a failure of communication to the player. Allowing the player to understand game mechanics without outright hand-holding or reading the manual is not as hard as Laidlaw is making it out to be. There are many, many games which are able to ease the player into complex mechanics gradually, and if you provide an option which cuts out a lot of the visible numbers and allows for auto-leveling, even rolling them in throughout the game at a measured pace, I don't think there will be a single player who is left behind... unless that player is a moron, but then, you can't please everyone, and shouldn't (but again, don't let that stop you, Mike!).
Here's an easy example which works in action games, and doesn't result in any depth being sacrificed: let's say my warrior is hacking away at an ice golem with his sword, but the blade clanks off it and he gasps "my weapon isn't doing a thing!" The player can infer from this, both with or without numbers, that his or her weapon is ineffective. Perhaps, then, a party member, or even a tutorial message, can say "Certain enemies can only be damaged by certain weapons. Try using fire to hurt it!" Now, the player has an understanding of a game mechanic: certain creatures are damaged by certain elements. Once the player switches to a suitable weapon, uses the right attack type, casts a spell, etc., the creature dies quickly and a character might exclaim "Hah, you're no match for me!" or something similar to convey that fire is not just effective versus ice, but more effective than a regular attack.
You say that think ice vs. fire and light vs. dark is easy, and it is, but once you've established certain relationships in the game, players are able to take an initiative and figure things out for themselves. Gamers are not as stupid as BioWare seem to think - a learning curve is always required to get newbies into a game, but once they've got a handle on things it's not long before they can figure it out. Extrapolation is a powerful tool for developers to use in teaching concepts to players. If I am introduced to the elements of ice and fire, for instance, I will quickly infer later on when water enters the picture that water is effective against fire, but is trumped by ice. It takes a pretty damn simple-minded player, even among action fans, to think that they should be able to get through the game via simple button mashing, and such rule relationships are quite common across just about all genres of games.
It's this sort of thing that I don't think BioWare (or at least Laidlaw) have a firm understanding of. Rooting game systems in common sense logic is an easy thing to do and works wonderfully, plus provides the depth that players need. The problem with RPGs in terms of accessibility has always been presenting information in an easy to understand sort of way, but this is something developers from all over have already managed to tackle and I don't think BioWare have any excuse in lagging behind (and they can't even get the interface they currently have right - see Dragon Age II and "two star" items being more powerful than "five star" items in some cases). When action games have more depth than your RPG once you hide the numbers, you know you've got a major problem on your hands - again, hint to BioWare: numbers only serve a purpose if they mean something! I can have 50 ways to make my numbers go up, but if the end result is identical and requires no variation depending on the situation, I'd might as well just have one way!
Now, there's the other issue here, and that's trying to reconcile a turn-based system with action-style gameplay. The simple fact is that real-time-with-pause doesn't really work in a turn-based setting. Origins tried it, and it ended up being a bit confusing for players expecting something more action-oriented; it likely would have fared better if combat was less point-and-click and allowed for more responsive controls for a more action feel, or had just gone full turn-based (or RTS, but let's ignore that since it brings in a whole other dimension). The thing about making an action RPG is that you basically just need to make an action game outright, and then layer the RPG mechanics on top of that. If you can't make one, you have no place making action RPGs, it's that simple. The depth in such games comes from character development, skill selection, non-combat gameplay, and so on, so in actuality it's even more work to make a good action RPG than a good turn-based RPG, or a pure action game!
So yeah, tl;dr post, but in summary: Laidlaw and BioWare have two options if we ignore the obvious issue inherent to compromise. One is to increasingly simplify game systems overall in the name of a small player base who are probably not very interested in your game anyway, and in doing so upset many of your other fans. The other option is to do a better job of hiding certain information in the game while still making it easy to understand in more visual, obvious ways that are intuitive in the same way many action games are intuitive - this doesn't hurt the RPG gameplay in the least, but still lets more casual gamers and fans of action titles play without too much trouble. Obviously the second one is better, and actually executing on it is a big problem that I don't know if BioWare are up to, but it's not something that can't be done - it just shouldn't come at the cost of game depth, which it did in Dragon Age II and it will continue to if Laidlaw is so keen on finding that "middle ground" which really does not exist in any truly sound fashion. Ultimately you'll be best served making one of three things - a full-on RPG, an action RPG, or an action game - and while trying to hit three or more birds with one stone might result in a few glancing blows, you're probably going to have to end up using three or more stones to get the job done anyway.