The statement I have an issue with is claiming that disruption was caused by apps needing to be rewritten for PulseAudio,

There's not any doubt about that. Things were broken all over the place until they were patched. It was awful.

which was most likely not the case.

It's weird that you're writing as if this was a hypothetical period that human beings did not actually live through, such that we can only speculate about it.