People complaining about graphics are literal children, but a lot of 80s/early 90s games really are killed by user interfaces and nightmarish controls.
The reality, though, is that when you finally manage to get to grips with the UI and master the controls, a lot of pre-Fallout RPGs just aren't as good as Fallout and its spiritual successors. Many are worth at least one playthrough, some are even great and belong higher in the Codex list than shit like The fucking Witcher and Mass Effect (lol). But in the end, I'd replay Fallout for the trillionth time before replaying Magic Candle, or Wasteland, or Realms of Arkania, or Darklands, or literally any Might & Magic game, or literally any Gold Box game, etc. There's exceptions to this rule, but by and large, the best post-Fallout RPGs are better than the best pre-Fallout RPGs.
New vs old cRPGs assessment aside (which I'm inclined to agree with), it's not just that 80s/early cRPGs "have bad graphics", technologically speaking. It's that most of them are fucking ugly in a way console RPGs really aren't. They simply aren't aesthetically pleasing. They are absolute eyesores. This goes for what
Zed Duke of Banville said as well: sure, a lot of 3D games look bad nowadays, but it's only the really awful bloom-abusing games (like Oblivion) that manage to become so ugly you can't ignore it, something that doesn't happen with Thief: The Dark Project for instance, or Deus Ex, or Gothic.
Fallout's user interface may not be good, and Gothic's may be terrible (in my opinion), but at least they are intuitive for the most part. Older cRPGs rely a lot on hotkeys, which explains why older Codexers tend to hate the lack of hotkeys in modern RPGs. But I'm the opposite: I grew up with a mouse and a keyboard, and that's how
I play my games; hotkeys are secondary to me except for the most necessary ones (inventory, journal, map). A cRPG that has no mouse is a big "no thanks" in my book, I'm hardwired through experience to click on stuff I want to use. And these older cRPGs tend to use hotkeys for
everything. I'm willing to put up with older console RPGs (assuming they are good) because the joystick makes navigating the interface very intuitive and simple. I can deal with the worst console RPG interfaces (looking at you, Dragon Quest) with arrows and two buttons (accept/cancel) but I can't deal with the hotkey-heavy interfaces of older cRPGs. Especially because these games don't offer what I'm looking for in fully fledged RPGs, which is less emphasis on combat and more on quests and story.
I believe this is the biggest culprit. For many people interested in RPGs the UI or graphics aren't the problem, they just can't be arsed to RTFM to be able to play the game. A shame, really.
Yet another stripe on the tiger, but what the hell: not having to RTFM is a good thing about nowadays games. It means you get to understand everything you need to understand as you play the game. No need to read info you don't need to know just yet. The issue with modern games is that you can't toggle off said tutorials off, but the tutorials themselves are a good thing.
A game that requires me to RTFM to know what the fuck am I doing is a game I'm not playing unless I'm
really interested in it, period. Unsurprisingly, none of the games in that time period you mentioned (1997 and on) require me to RTFM, because they are intuitive enough.