> Fonts should be provided by the website

No way!

I don’t ever use any font provided by the website. I don’t even let websites choose which fonts get used. Instead I choose a set of fonts (monospaced and proportional) that are readable and everything uses those.

If you want to see what that looks like, go into the Firefox settings, find the Fonts section, click Advanced, and then uncheck “Allow pages to choose their own fonts, instead of your selections above”. Be sure to adjust the “Minimum font size” while you’re here so that nobody uses text sizes that you cannot read.