

A big feature AND problem with the live-service market is that gamers STAY engaged with the games. The majority of players play your random RTS for a few weeks, maybe a month, and then move on. But these live service hero shooters keep pumping out content to keep players invested and build in a ton of engagement sinks so you won’t leave.
As a result, you can’t have “The next Marvel Rivals” like you had “The next Command and Conquer” or “The next Battlefield”, because everyone is still playing the current Marvel Rivals. That results in a completely saturated market. If you want a player, you’re going to have to drag them away from their current game, which they’re comfortable with and have a massive investment in.
If you’re releasing the next Assassin’s Creed, you don’t need to be amazing, you just need to wait for people to finish the last one and deliver something pretty nice. Maybe it’s better, maybe it’s worse, but the field is empty so who cares. For Live-Service, you don’t just need to be better than the rest, you need to be sufficiently better that all the players are willing to abandon their huge investment in the other game and switch to you.
And well, your game might dissapear any second, while their game has been around for years and surely will stay around foreeeever.

Also, live-service games endeavour to stay relevant forever.
For, say, God of War, you’ll eventually be done with it. You’ve played all the things, you put the box on the shelve and move on to another game. But for these forever-games, you can play them forever.
And that means that if you want to launch a game in that market, you can’t rely on getting players who just put down God of War and want something roughly similar. You need to not only be better than Fortnite, but you need to be sufficiently better than people will abandon years of investement into Fortnite to go play your game.
The barrier to entry is HUGE, and it’s made much worse by the idea that the new game might dissapear, meaning you wasted months (or, occasionally, days, lol).