I can see a lot of people no longer finding the decomp projects enticing when most of what they see are vibecoded projects

I agree with you here. In fact I wanted to express this issue first. But it made my previous reply complicated to understand, so I left it out. So yes, that's one of the issues. Also if a game is already vibe coded into a recomp, then someone else might find it less interesting to tackle that project, because most people probably wouldn't find it interesting anymore (as there is already a port). Which would be a shame to be honest. So yeah it's not all good only.