I can’t speak authoritatively to the micro computers, but I’m under the impression that the Atari line of 8-bits was never very popular in the US. I’ve always gotten the feeling computers played second fiddle to consoles once the NES arrived until the IBM clones started to get good at games much later.
I know the Commodore 64 was somewhat popular. There were other computers with games but I don’t think any of them had the capabilities the C-64 did (Apple-II, TRS-80). The ZX was released under the Timex brand but like the Atari I’m not sure it ever went anywhere.
From the history I’ve read I think part of it may be that Atari was just kind of a disaster here. The fact that Atari actually had popularity in Europe plus they could probably make their own decisions without interference from Atari US may have been what allowed them to succeed in Europe. But that’s a guess.
I think the ubiquity of the NES in the US impacted sales (and therefore software availability) of the Amiga and Atari ST as well.
Sega only began to gain mindshare with the Genesis (the US counterpart to the Mega Drive.) So, Atari has a very old retro cachet, and Nintendo has a solid hold on nostalgia from the late 80s on.