That's survivorshop bias. Yes, occasionally a fork takes over. It very rarely succeeds and usually only in cases where the original is so toxic that it cancels out its own network effects. node.js is a good example of that. And then even there note how they eventually unforked.
It is really uncharitable to describe the node fork as "so toxic". People disagreed, but there's nothing wrong with that. I felt like the subsequent "merge" happened fairly quickly and with minimal drama.
Also this seems like a misuse of the term "survivorship bias". You claimed upthread that forks don't work because of network effects. The response was "some forks work". That is a direct refutation, no matter what the percentages are. Besides, you're misunderstanding the varied purposes of forks. I have several forks right now, not because I hate the original maintainers but because it was convenient to change a small thing for my own purposes. Whether or not upstream eventually agrees with me, my fork "works" perfectly well.