It’s mostly a problem for indie games where novel gameplay is often the main selling point. Imagine if a hundred Katamari Damacy or Patapon clones came out months before the originals, and whether they’d have made the same impact when they finally released in that scenario.
Clones are already a huge problem in the independant games space (see the myriad of “dig for buried treasure in a backyard” games last year). AI gives cloners the ability to churn them out so rapidly they can steal the original’s thunder entirely.