Even if the courts won't uphold the copyright, that doesn't prevent people from claiming your videos and initiating YouTube's copyright process against you. This is a recurring problem for people who upload their own original performances of public-domain compositions, particularly solo piano.

Indeed. False copyright claims should be illegal, they're an invitation to fraud.

What if you claim it first against them? You wouldn't be punished for a false claim, since they're not.

uhh, no

Reasonable people can believe they have a legitimate ownership right when they petition YouTube for copyright enforcement for AI-generated work. The courts might eventually disagree, but that's a different thing than knowingly making a fraudulent misrepresentations to YouTube for financial benefit. This difference makes the proposed behavior criminal fraud. I highly recommend not risking twenty years of prison time for like maybe a couple hundred dollars in ad revenue.

It's not knowing misrepresentation. You AI-generated the same video, so how were you to know it wasn't yours? Just don't show them this HN thread.

Besides, nobody's actually checking

An often repeated talking point that's broadly false without further context. Mechanical output on its own can't be copyrighted, that hasn't changed. However it can be if sufficient (as determined by the courts) human creativity went into causing it to be output.