A myriad of small businesses also use Facebook as their public facing website.

Only out of convenience. There are many alternatives, and search engines will find them. And (although it won't happen) if Facebook were ordered to shut down, hundreds of entrepreneurs would offer alternatives for "small business web presence"

I find that truly mystifying. I won’t go through the hassle of opening an account on any platform just to see some dumbed down website. I can’t be the only one, can I?