Not supporting SNI is the browser's problem IMO, because SNI are required to enable a single IP to host multiple HTTPS websites. SNI is not just for CloudFlare.
(Does PyPI need to host multiple HTTPS domains?)
You're missing the point. "It doesn't matter why they're dressed as a tiger. Have they got my leg?"
The real question: is the PyPI front page running on someone else's infrastructure or some dedicated hardware?