This html page comes from a vscode snippet using the builtin "!+tab" combo.

Also check out /firebase which is the page generated by the firebase CLI. It was created running firebase init and selecting the firebase hosting service.
This is a CDN service by google with builtin SSL and autoconfigured cache headers, for blazing fast and cheap delivery, accross the globe.

But it only works with static content, after all: it's not a web server. Everything dynamic has to be done client side.
I have to admit I still don't fully understand how this is best practice. But im going to stick with it, because I want to work with vuejs, serverless SPAs ftw I guess.