Some other incentives are balanced, though. Persistent low performance or bugginess affects the author and end users equally; the more the author uses their own software, the more this will hurt. Sometimes the low performance is a design trade off; Python isn't Rust, and the users seem to be okay with that. It was done on purpose. Sometimes low performance is a factor of the author's needs; you're trying to run the thing on 1 billion machines, they only have 1; something has got to give. But that's not misaligned incentives so much as it is lack of suitability for a particular purpose. A screwdriver is terrible for hammering in nails. That's not the screwdriver's fault.
It's really hard to tell what the motivation of any given free software author is. That makes it really hard to even know what incentives matter to any give author, team or community. It's just really diverse.
> That's true! But there is almost no incentive to have users; you pay a cost, but they pay nothing in return.
It's fascinating to see free software with huge user bases getting on with a tiny number of contributors. It seems like good code + near zero support cost + near zero support expectation seems to work.
FOSS software has vastly different incentives than commercial software, yet suffers from many of the same problems: bugginess, poor performance, lack of documentation, feature misprioritization, bad UI.
That alone indicates that the problem is not merely "misaligned incentives".
Actually, you can reduce most problems down to "misaligned incentives" if you're overly reductive enough. That doesn't mean that it's a useful way to think about the world.