It's worth asking "if AI is so great for software development, won't that make it dramatically easier for people to maintain their own forks of software?"
(I suspect the answer ends up being no, but the reasons could be interesting)
I'm curious why you think the answer would be no. I've had some success with resolving complex merges with GPT 5.4, and it seems obvious enough that AI is a good solution for maintainers who don't have anyone they can trust to take over the project whilst also needing to boost throughput.