I've never found page speeds to be slow, including through a VPN. You can also get Google AMP versions of Medium pages if you find the articles that way on a mobile device. AMP will prevent React from loading so that should fix any page load speed issues.

There's an AMP extension for Chrome that does the same thing https://chrome.google.com/webstore/detail/amp-browser-extens...

I think the searchability of the textbooks via Google is a big pro in favor of them going to Medium. And personally I like the interface, but to each their own I guess.