> Under your logic someone playing a CD is a musician.
No. That isn't my logic at all.
> Just pasting a rehashed joke as a genAI video prompt is not much of a creative process.
That isn't what is happening. What people are doing is taking people from different online streaming shows, making new content based on jokes made on those show and turning them into music videos, which are usually a cover of a well known song.
People have been doing this online without AI for quite a while. Usually this was with various music software. All AI does, it make this process easier.