This is really just an awful idea. Every few weeks/months I see some kind of "wouldn't it be great to have users write pseudo-html in json and we can then write

This is really just an awful idea. Every few weeks/months I see some kind of "wouldn't it be great to have users write pseudo-html in json and we can then write loads of javascript to write the html for them!" kind of library and the answer to that is always "why would that have ever seemed like a good idea?". Good libraries decorate html to provide functionality because, well html is pretty good at the html bit.