I disagree. There are some new (sub-) genres and great games since that period.

* Roguelites have proliferated: Hades is the most obvious example, but there are a variety of sub-genres at this point.

* Vampire Survivors (itself a roguelite) spawned survivors-likes. Megabonk is currently pretty popular.

* Slay the Spire kicked off a wave of strategy roguelites.

* There are "cozy" games like Unpacking.

* I don't recall survival games like Subnautica or Don't Starve being much of a thing in the PS2 era.

* There are automation games like Factorio and Satisfactory.

* Casual mobile games are _huge_.

* There are more experimental games, sometimes in established genres, like Inscription, Undertale, or Baba Is You.

Not to mention that new games in existing genres can be great. Hollow Knight is a good example. Metroidvanias were established by the SNES and PS1 era, but Hollow Knight really upped the stakes.

I'm sure I'm forgetting things and people will have some criticism, but I really don't believe games have stagnated in general.