I mean the definition by MDN, however I like to focus on disabled people and bots, since these usually are the critical groups we tend to forget and the former are the legally important ones.
As for accessibility features, if you want to write Angular code but have to keep in mind tools which cannot use JS (or only to a very limited degree), then you will have to ditch all the major features of the framework, which makes me wonder if Angular was a fitting framework for the project in the first place. It's important to use the right tools for the right job! Don't put a screw into the wall with a hammer, just because you like your hammer.
As a side note: Personally, I don't like SSR, because it wastes many CPU cycles and someone has to pay for that on top (it's a static site, why not finalize it at build-time? Why do you need dynamic generation of static content?). Also SSR introduces a new attack vector - it's software which can fail.