People can find satisfaction in various hobbies despite the fact that there are people who are better at those hobbies then them. People can also find satisfaction in those hobbies without the need for approval from others. Most of the amazing things people do, are not done for the purpose of seeking money, so I don’t see why you think that when a UBI happens suddenly everybody will become a porn addict with no drive to do anything at all.

You seem to have a very specific, negative idea for what the future holds, but it doesn’t feel like one based in reality.