I have a rocky relationship with social networks on the web. I periodically have social fatigue and thats when I usually delete accounts. I did this many times with Facebook, Twitter and even Mastodon.
Mastodon however is special, since it is a federated network of different instances, and works similar to email. You have an account on instance x, but you can communicate with other instances. And because the whole thing is open source anybody can start an instance. It is a lot of work being an admin, so only if you want something small, or just a single user instance for yourself, that's when I recommend do it on your own.
There are different instances with different interests, but people usually don't post about just of that specific topic. You can register to many instances, and you can use the same username.
I use mastodon.social the biggest instance I think at the moment. When you use the search function it goes across every public instances though. This is one way of discovering interesting people. You can only search for hashtags or for people, which at first looked very limited. In this way people use hashtags more and with purpose, and I rarely saw spam,
So far I met mostly friendly people, so my experience is 95% positive. That 5% happened when I first registered to Mastodon, but I am over it. I have learnt to not post about certain topics.
I like that there is much less drama on Mastodon than on Twitter, probably because it is much smaller. I don't care that I can't follow celebrities. I purposely don't talk about politics, and other hot topics. The only touchy topic I talked about is fatacceptance and weightloss, and I got few favorites and boosts (retweets in Mastodon lingo).
In the end Mastodon is what you make it. It depends on you, how you build your network. This time I use it much slower so when I look at my timeline, they are full of people who worth following. I don't follow people just because I found few messages from them, interesting. I look at their recent activities.
Mastodon is free to use, and on this site you can get a fresh list of instances, or you can take a test, see if you can find anything interesting.
If you don't like the default web client, take a look at pinafore. It is a single column, multi instance client.
Mastodon is less drama, and more interesting people! You can reach me at firstname.lastname@example.org.