word clouds will find when a corpus of hashtags is similar in meaning. If you use only hashtags, that's like experiencing a grocery store or farmers market via an ambassador who cannot see the serendipitous shops that are nearby, the things frequently seen together. It's like shopping in an app and never visiting the grocery store itself. Having a precision following list means you can't experience going to a library and browsing shelves until something catches your eye - serendipitous search is fundimentally different from subscribed/reposted delivery, or even keyword search.

computers and digital space don't natively have the metric for which hashtags are closer, so they have to crunch the numbers to help figure out which books are closer to other books. Otherwise it's like entirely separate universes that you'll never ever find, like if you never knew a word that would lead you to a community of much more words and concepts and free thought.