They're just like Hollywood blockbuster execs. They'd rather one game that copies what they've identified as popular from other games and media to formulate a game that can make hundreds of millions in profit if not into the billions rather making a bunch of smaller games that can make smaller profits. Single to double digit million dollar profits. It'd take a large amount of smaller hits that they can't imagine managing to accomplish to equal the profit of one mega hit so go big or go home. Unless you're Nintendo, they churn out smaller games and they have a brand/game identity that people generally don't seem to be let down from. They're consistent

Go from the summer blockbuster equivalent holiday AAA graphics bonanza game where the rest of the year was filled out with cheaper bets to any month is a month for a blockbuster/AAA game. Well, graphics don't sell games like they used to so you get these multi hundred million dollar budget games struggling to sell any better than AAA games made in 2007 that were made with a fraction of the modern AAA team size and made in like a third of the time to development