Most “hardcore” gamers, as in you are well versed in your specific genre of games, can only sustain the grind of 2 live service games, More than 2 it’s pretty much consume more hours than a full time job. So as far as I know current category of gamers are in one of following categories, with exclusion of youtuber/twitch streamer etc as they are paid to play whatever they collab with or fan/chat request, etc. (also not including mobile gamers.)

1. Gamers that only play competitive games, aka grinder, in a phase thinking they might go pro some day so all their hours are dedicated to get better at 1 game or that genre. (FPS: CS2, Apex, etc. Moba: Dota2, LoL. Fighting Games, Rocket League, Deck building etc. They might try out some newer game in their genre but usually just to see if it has potential to become next hit and see if they can get something out of it if they are relatively good with the game. (they sell accounts of their “test” period with higher rank first season rewards, pre-order bonus, beta test rewards etc. )
2. Gamers that have 1 “main” game from above, but also player other games from different genre. Main game’s “up time” dependings on the gamer but usually it’s to play and unlock stuff/progress for the season, ie. Season Pass from Fortnite, Rocket League, etc. Genshin Impact, or content/gatcha with time limited events games. Then play whatever other games they want in the “down time”, like say when Elden Ring released, most of gamer in this category that interested in this genre will play it, get enough of it then get back to their main game. If they have PS5 they might be playing Spider Man 2 at the moment for example.
3. Gamers that do not have a main live service game, their main is the current “trending” games, the hype wave riders, most likely have active game pass(es) sub so they can just catch whatever they can. (It’s like keeping up with the TV shows, but this type of hardcore gamer just spend most of their free time to get as much current trending game exposure as possible, maybe streaming with <10 viewers count.)
4. Gamers that are completionists, they beat 1 or 2 or 3 games at the same time but 100% and retire them from roster, then replace with whatever their next target is. Achievement/Collectable hunters, doesn’t matter with the difficulty of the games. They probably won’t play any of the live service game as they are holes that will never be filled. Most videos of 100% run, all chests location videos are from them.
5. Gamers that stick to their specific genre’s top games or speed running them. Ie, Monster Hunter game’s speed runners. God of War 2018 speed runner, Souls no hit run, they play 1 game thousands of hours and find exploits and glitches etc and do crazy shit that might require frame perfect inputs. MMO’s that have many accounts level up to max for each class.

Other than these, I don’t consider the rest “hardcore” gamers, as they might have other stuff they enjoy thus gaming aren’t the focus of their leisure time. As casual gamer, they are not committed to a genre or a game enough to stick with it long time, thus even if it’s f2p with season pass or whatever fomo, it’s hard to get money out of them compare to the hardcore cat 3 ones. And out of all the above 5 categories, what live service want to capture is the “whale” category. They don’t actually have the time to commit like hardcore gamers(unless they are from UAE), so they just buy their way to the top, spend 200~2000 on one game per season is normal spending to them. And sometimes they will have the “whale” specific gatcha/drops. Like brands that release designer bag in limited quantity cause they know their market’s whales. And whales is probably an off shoot from cat 3 and may or may not bias into other category depending on what they think if it’s justified.(UAE players is hard to category into types, they are their own category, they are “the” whales).

New live service games can only capture cat 1/2/3 temporary, IF they beat the top dogs in their genre, then they become the new status quo. It’s very hard or almost impossible to become top or beat the top in cat 1 and 5 cause fan loyalty. (like imagine beating CS2 or Dota, or say take away 10% of their market share. ) Cause, it means, to give up all their time/money investment and switch to yours, and face uncertainty. If your game folds 3 years later with bad decision making their time/money is wasted. All “new” live service needs to navigate how they can trigger a switch from those gamers, and keep in mind that cat 3 players only gonna ever last a while.