It's hard for me to put this in a short response. Gaming as a hobby is more mainstream than it was 3 decades ago, and our general culture has gotten softer. There's always been the Eternal September effect, where pioneers in an area of life have said thing experience rapid growth of newcomers. Overwhelmed by sheer numbers, they aren't able to acculturate the masses with healthy norms that ensured the success of said thing or community in the first place. With games in particular, monetization shifted towards post-purchase micro transactions, so devs put more resources into retaining a lowest common denominator playerbase, oftentimes with whales. This coincides with the general cultural shift of expecting competency (or in-group compatibility) towards unqualified inclusivity, even when said inclusivity weakens a hobby or makes it dangerous (ex: skiing and snowboarding at a popular resort). This effects singleplayer and multiplayer games, like Total Warhammer removing what little campaign logistical depth there was.

Multiplayer games in particular shifted away from the high-skill, always alert Quake/Unreal. Battle Royales (disclaimer: I've play them for 40 hours at most) are the prime competitive example, where one can relax and mess around. But a player struggling to win can blame their teamates or random item spawns instead of their own lack of skill and coordination. MMORPGs forever changed with the massive success of WoW which, despite being skillful game, was a casualification of earlier MMOs; this got much worse past the 2nd expansion. I'll explain further down.

Just looking at the Guild Wars franchise alone, the first and second game are stark contrasts. GW1 is basically a party RPG with shared lobbies, and GW2 a regular themepark MMO. The first punishes you if you try to level without any thought put into your skill selection and traits, and required you to find other players to progress missions, or rely on AI henchmen. The game did change with expansions introducing heroes to make other players unneeded (this had to be done as content grew and playerbase shrunk), while certain infamous missions like Thunderhead Keep got nerfed.

The second game targeted the wider MMO audience and changed industry trends. Starting off, they neutered any leveling or open-world that they were afraid scared off enough casual gamers from other new MMOs. IIRC during the beta, there was a trio of Ettins guarding a hero point (needed to make character stronger before reaching level cap) that stunned players (each would telegraph their attack sequentially) that didn't dodge or block, leaving piles of player corpses. Stuff like that had to go to maintain a soft leveling experience. There's actual skill and creativity in the game mechanics and buildcrafting, but most the time it wasn't needed, leaving a large gap between launch content and intro endgame, in addition to an equivalent gap and good players doing the rare slices of challenging content.

With the advent of political correctness, cultural Marxism, and similar coincides with the above to have a multiplayer and MMO scene to replace the declining past-time of watching network television. Whether it's Bob who instead of plopping down on the couch to watch Jerry Springer, picks up the latest game to not talk to anybody or learn mechanics, if the game has them. Or it's Jeff, who instead of watching the latest sportsball game with his buddies heads to a multiplayer game to bad unskilled while downing a few beers and having a grand ol' time with other online folk. This creates a giant vacuum to be filled activists, hall-monitors, or opportunistic devs can be 'anti-gatekeeping' gatekeepers, who then cultivate what I call a gaming underclass to steadily build-up and be exploited. The hidden costs of this dysfunctional social structure accumulate until playerbases of games result in swathes of shit, whether it's the mishandled toxic players, a lopsided skill distrubition, and an over-representation of what Javier Milei deems shit-leftists. It wasn't nearly this bad in 2005.