Ohhh derp for some reason I didn't even suspect hashtags were a thing on NOSTR... thanks for the tip!
Discussion
I don't think all nostr client support following a hashtag. But I know that #amethyst and nostr.kiwi does
Not sure about the rest
Most now support hashtags.
hashtags on here work better than they every will on Xtter. You can even follow specific tags with any feed reader or create your own. check out https://feeds.nostr.band