Mine was Mastodon a few weeks before the Twitter migration while searching for alternative platforms. Came back on the migration after elongated Muskrat takeover. I tried to find anyone who have the same topics as me on Friday after that migration but no one came out.
I came here when I see a post on Masto about Reddit charging their API. I immediately created a community after registering my account.
I forgot about PeerTube about where and when did I found out about it, but I remember when I first registered in a Spanish instance but I felt like it was defederated by most instances so i find another instances and registered on an Singaporean one (same username).
The problem in all of those platforms, all in my case are no one or too little people are there for my topics, but despite those issues ill never leave.