I was annoyed too when they started to close off HTML as a local platform.

But! it is still very open (you complain about audio and javascript but they both work) also I've figured that it isn't really much of a problem to start a python/node webserver for the things I'm not allowed to do. Literally a fraction of a second. Just set up a "webserver_here" command in your terminal, or keep one running constantly. Also I'm starting to fear local HTML more and more, I'd actually be happier with a much stricter boundary.