i was invited to a tiny little mastodon instance that a friend of a friend was running back in, like, 2018, and i couldn't get into it at all. i got that it was federated, but the global timeline even back then was just a constant stream of noise, and the instance was so small that the local timeline was just the same handful of people talking to each other if i remember correctly. i also didn't really like mastodon, but i had no clue that there was other software i could try. i didn't use it much. and then four years later i wanted to try again by joining a bigger community and made the classic mistake of signing up for the flagship mastodon instance, which was of course even worse, haha. but then a couple months later i learned about misskey, and that's what made everything click for me. the rest is history basically.

it took me a little while to finally land on an instance that i felt at home on because i am so miserably anxious all the time, but i'm glad that i kept searching!

(also this is only tangentially related to your question, but this being my experience is exactly why if i'm ever trying to help someone join the fediverse, i tell them to choose what software they want to use first and then look for an instance. fedi is so often characterized as being Just Mastodon that of course i thought mastodon was the only option back when i first joined and wasn't very familiar with fedi. discovering misskey made such a huge difference for me and i'm sure it would have helped me a lot to have known about other fedi software from the start.)