To make people more accustomed to the AI generated look so that when they release their next Veo integration to YouTube content creator tools, these videos will stand out less as unnatural.

Sadly, this is a real possibility. I would even conjecture they are testing a new pipeline, in which the input is real videos and the output are AI-generated.

For now it's a kind of autoencoding, regenerating the same input video with minimal changes. They will refine the pipeline until the end video is indistinguishable from the original. Then, once that is perfected, they will offer famous content creators the chance to sell their "image" to other creators, so less popular underpaid creators can record videos and change their appearance to those of famous ones, making each content creator a brand to be sold. Eventually humans will get out of the pipeline and everything will be autogenerated, of course.

To me, this is the only thing that makes sense. Why else would you spend so much money doing this?

There's also the on-by default, can't be disabled, auto-dubbing YouTube performs on every video that's not in the single browser's language. The dubbing quality is poor for the same reason, to intentionally expose viewers to AI content.

It's 100% a push to remove human creators from the equation entirely.