That's not really true if you care about reliability. You need 2 nodes in case one goes down/gets rebooted/etc, and then you need a way to direct traffic away from bad nodes (via DNS or a load balancer or etc).
You'll end up building half of a crappy CDN to try to make that work, and it's way more complicated than chucking CloudFlare in front of static assets.
I would be with you if this was something complicated to cache where you're server-side templating responses and can't just globally cache things, but for static HTML/CSS/JS/images it's basically 0 configuration.