I suppose one argument might be versioning, (some) fonts do get updates (and js libs should, you'd hope), they'd either have to ship those with OS updates or le

I suppose one argument might be versioning, (some) fonts do get updates (and js libs should, you'd hope), they'd either have to ship those with OS updates or let them rot. And of course it would make those updates bigger, which would use more bandwidth and thus energy...