Wow, I'm realizing this applies to even browsing files in the web UI without being logged in, and the limits are quite low?

This rather significantly changes the place of github hosted code in the ecosystem.

I understand it is probably a response to the ill-behaved decentralized bot-nets doing mass scraping with cloaked user-agents (that everyone assumes is AI-related, but I think it's all just speculation and it's quite mysterious) -- which is affecting most of us.

The mystery bot net(s) are kind of destroying the open web, by the counter-measures being chosen.