You don't need a plane to get from America to Europe, but there are constraints if you don't use one.
I think most people are angry about the artistic portion like images and dialogue of games being AI generated more than the code. Code can be art as well in my opinion, but it still can be even if you AI just ported a large part of your code base to another target engine for example.
Doesn't prove anything, lots of stuff changes development house tempo, but to anyone watching things as a whole updates across steam games in active development are 1) quickening 2) narrowing 3) becoming predictably scheduled ; all of these point to more than just a single group refocusing on the work at hand.
I think builds are getting pushed out a lot quicker, and personally I know of a lot of anecdotes where groups' entire build and output chain are handled by LLMs invoked by cron (or a clone). That alone will add a lot of regularness to things.