I thought it did in fact catch on but most people still referred to it as "RSS".

I think it caught on well enough, platforms such as Wordpress still support it out of the box (I just checked my blog, it works).

I liked Atom's clean design but it felt it was mostly pushed by Google (I may be misremembering) and in the end the syndicated web faded into obscurity anyway.

Docusaurus supports it out of the box as well https://docusaurus.io/blog/atom.xml

IIRC RSS 2.0 included most of what Atom has, no?