en.wikipedia.org has around 260 million page views per day. Each page view consists of multiple HTTP requests (picking a few random pages shows twenty or more per page) - so I'm pretty sure that wikipedia has higher traffic figures.
Both wikipedia and pypi requests are >99% readonly and cacheable, and neither have strict global consistency guarantees. That makes them very cheap and technically easy to run through a free global CDN like cloudflare.
It seems wikipedia english gets 255m per day. This doesn't include all of their image hosting and other side services though. I think those are in the many hundreda of millions if not billions. Id say they are at least comparable.
It's kinda moot though. I wouldn't begrudge pypi asking for money either.