Ok, throw in PKM and WotR. Are they better?
Why do you keep citing RtwP games, it's impossible for them to be better since they're RtwP, they lose by default. Pathfinders do have harder combat, but it's not a good combat, you pretty much don't do anything in actual encounters, it's just a benchmark to test your build and the entire work is done in the character inventory and lvlup screen. Buildfaggotry aspect is much better than BG3, and can be very fun for some time, but obviously it's not a great approach overall, when combat itself sucks.
My point is you already know what system the game uses and how it works, so what's left is designing the encounters uniquely. If you are super experienced with D&D games you know the synergies, the counters, and the "meta". Designing encounters for this kind of player just turns into an exercise for the designer to one-up you in his munchkinism, while still allowing you a narrow margin within which to "beat" him, because after all, you're the player.
Yes, and I already told you encounters are designed relatively well, the problem is fine-tuning and balancing the numbers to make that work shine. It's a well known problem in online PvP games, sometimes a very small change to numbers, can have insane impact. Pushing damage on a skill from 45 to 50 might seem like a small change, but it might be a difference between needing 2 or 3 applications to kill a 100hp character, actually ending up as a massive change. 5E combat can snowball really quickly, and some relatively mild rebalancing of enemy stats and xp player gets, could result in a massive improvement to the quality of Tactician combat.
And much to no-one's surprise, this mainstream oriented BG3 doesn't include the equivalent of Unfair difficulty from the Pathfinder games.
The reason I never gave Tactician a try is exactly because I've spent enough time in other games, trying to find satisfaction in the max difficulty level. By now I know that there are RPGs where it makes sense to try harder difficulties, ones where a harder difficulty is a good idea for a second run, and ones where the higher difficulty is badly implemented and only tests one's autism. My estimation is that BG3 is in the best of cases in the second category. But for a first run, I'd rather go with the difficulty the designer expects the average player to take and has tested the most.
No one expected Unfair difficulty, but I thought it would be similar "challenge level" to Pathfinder on Core, which is comparable to how the tactician felt in DOS 1/2, eg. no need for hardcore minmaxing, but requiring some thinking on lvlups and in combat, and getting you excited about advancing in power and getting new items. From interviews pre release, it seems Larian also wanted it to be that. So if I and other tacticool players find it easy to the point of being brainless I see no problem with bitching so Swen maybe fixes it. If not, I'm sure modders will do it sooner or later, but obviously it'd be preferable for the devs to do it.
IIRC Larian is supposedly using heat maps of players deaths and shit like that to decide on balancing, and I suspect that players on Tactician might actually be dying far, faaaaaar less than people on lower difficulties (I legit had to reload a fight only 2-3 times during the whole playthrough, and it was mostly due to me playing on autopilot and doing something retarded) since they're generally people who played shitloads of turn based games, while quite a lot of normies on easy/normal will be making beginner mistakes that will get them killed regardless of difficulty level, so I really expect that Larian will actually see the stats showing Tactician as piss poor easy, and decide to rebalance.