I've also seen a few game devs saying ECS are useless in quite a few situations (or, at least, a very zealous adherence to ECS).

I guess it's one of those things that you don't know until you try (and hit the limits of using or not-using one).

I'm also reminded of Robert Nystrom's "Is There More to Game Architecture Than ECS": https://youtu.be/JxI3Eu5DPwE

(Yes, Robert Nystrom of Game Programming Patterns and Crafting Interpreters)