TBH, I'm still not aware of any truly simple/easy way to get a dynamic HTML page.
Recently, I had to make a dumb utility app to render some dynamic data, and I wound up writing a Golang server with the HTML specified as a Go Template. But making it accessible on the publc internet still required spinning up a server, installing nginx, configuring SSL with Let's Encrypt (at least it was free) and futzing around with nginx `proxypass` directives for several hours.
It works, and I guess it's conceptually simple, but it was still an all-day ordeal to get it up and running from scratch.