I am claiming, though, that amateurs and enthusiasts are incapable of contributing to state-of-the-art AI. There is too much accumulated knowledge. If it was a low, but possible, chance to just make AGI from first principles it would have already happened sometime in the last 50 years that people were working on it. If, however, it is like every other field of science, you need to build the next thing with at least deep understanding of the previous thing.

Your examples might not have had a lot of money, but they all certainly were experts in AI and knew what they were doing.