Well, technically the reason for the fork was the implanted backdoor that was executing a binary coming from Muse groups server, hidden as telemetry and an update check. It's not a well built backdoor and the code is easy to spot, as there's not a lot of other http related code in audacity itself.
edit: Check the au3/src/update/UpdateManager.cpp, they're still not hiding this better after all that happened, lol.
[1] https://github.com/audacity/audacity/blob/8d6e45a9756e700b7f...