technically speaking it's "not just a sharpening filter", sure. but practically speaking it's not really much more than that.
it does have the ability to look for geometry edges and smooth them while increasing their resolution.
but in practice it's just a slightly more sophisticated sharpening filter.
and it's also not really related to FSR2 in a technical sense, it simply shares the same name.
after being subjected to Jedi Survivor tho, I'd take a raw 720p with zero AA over FSR2...
just a reminder what FSR2 at lower resolutions looks like:
it's like if you use a really low quality JPEG compression on an image

in motion it's even worse, because what you can't see here is the pixel fizzling in motion