Per-site caching negates the principal selling point of centrally-hosted JS and resources, including fonts. The convenience remains, but all speed-related perks (due to the resources being reused from earlier visits to unrelated sites) are no more... which is actually great, because it reduces the value that unscrupulous free CDN providers can derive from their "properties".
It also means that I can remove fonts.google.com from the uBlock blacklist. Yay.
It also means that I can remove fonts.google.com from the uBlock blacklist. Yay.