AAA games take longer than they did a generation or two ago.
Insomniac and From already had a bigger team capable to work on 3+ games at the same time at the start of the previous generation, SSM and ND not, they did prefer instead to have a single bigger team.
In the Jimbo era, after releasing TLOU2 in 2020, ND grew from being able to work in a single game to be working on at least 3 new games (TLOU Online + at least 2 SP games) + supporting remasters/remakes/ports/movie/tv show. The remasters/remakes/movies/tv show only require them a small portion of their team because they are mostly done elsewhere, but give them extra profitability that they need to fund their big games. And is work they do, so they do count even if obviosly not as the same as the big projects.
SSM grew to be working on -at least- 2 new games (GoW + new IP) plus Valhalla and supporting the PC port(s).
Jim and Hermen did fund them grow to became in a few years over 3 times as big as they were. To grow a studio isn't just to put more money to hire people. As the studio grows the are many changes related to management, organization, processes, studio culture, etc. that require some time of adaptation, you can't grow too fast because many things can go wrong.
ND does the games they want. They wanted to make these 3 games, but later realized that to do the GaaS properly they'd have to dedicate it more resources than they originally though, which would affect the other teams. Something they didn't want because they want to focus on SP games, so they killed the GaaS and will make another SP game instead.
Sony isn't mismanaging them, they broke sales and GOTY records with their most recent game and even with the movie and TV show. Plus did help them grow to work on more than 3 times the stuff they did before.
The costs of these big AAA games is so expensive, the 3 main games they were working on pretty likely did cost over a billion combined, and they have to consider that from time to time some game gets cancelled (like TLOU Online) or tanks in sales. And aren't the only ones, PS Studios has over two dozen games more under development plus the Bungie ones. So it's a big risk and there's finite money, so they have to be careful.
These ports/remasters/remakes/movie & tv show adaptations require very little work from ND because are mostly done in other studios and are very profitable for them, which help them be more safe if some game tanks or gets cancelled.
I'd bet that their next games will be:
- Uncharted 5/spinoff - 2026 (the project they started with Bend)
- New IP - November 2027 (crossgen launch PS6 game)
- TLOU 3 - 2028/2029 (crossgen, partly refurbishing story and assets made for TLOU Online)
Somewhere in this or early next generation, mostly developed by external studios:
- Uncharted Nathan Drake Collection (remastered for PS5 + PC)
- Uncharted VR spinoff by Firesprite (think an evolved Horizon CoM)