Welcome in, o dismayed souls, to a slightly kinder version of social media. A version not controlled by corporations, or even medium businesses (unless they have their own instance for their employees...like journalists.)
You've probably made your first #Fediverse account on #MastodonDotSocial - and, hey, that's a way to get started! But after a few months - or a few days if you're feeling particularly adventurous - you may want to move to a less-populated server.
There's nothing inherently wrong with mastodon.social, or with any of the other instances controlled by Eugen / Gargron.
But one of the "hidden" strengths of the #Fediverse is that it's spread out. It's distributed. If one server is knocked offline or bought out, the rest of the fediverse keeps on a keepin' on. All servers are connected. It's like a #MycelialNetwork
Just find yourself a new home and migrate your account. You'll bring all of your followers, even leave a forwarding address.
Mastodon is one app in the #Fediverse. It isn't even the only microblogging app - there's #CalcKey #MissKey #Akkoma and other forks of Mastodon. And, yes, they all talk to each other; and since they're all forks off of the same source, you can migrate from Mastodon to CalcKey (just to pick one.)
But wait, you cry. I just got here! Why are you telling me to #migrate straightaway? Is something wrong????
Technically, nope. Mastodon.social has operated smoothly for a long, long time. The owner of #Mastodon software has turned down buyouts. But others in the #Fediverse point out - if a server does get super-huge, they're a VERY tempting target.
So...just avoid making that server - or any server - a tempting target. When choosing a home server, look for userbases of 100 to 1,000.
You don't have to keep moving every time your local instance gets more than a thousand users...but if it gets over 50K, I personally would be cautious. Being on a 'critical-mass' server doesn't make you any more visible.
(Also, find ways to #contribute to your local server admin rather than just to Mastodon itself. I personally am on my local instance's Patreon, and have given a one-off donation to Masto itself.)
There are several guides on migrating from one Mastodon server to another - here's the one I used when my first instance announced its closure:
https://allthings.how/how-to-migrate-from-one-mastodon-server-to-another/
(And, yeah, server shutdowns may happen from time to time. My advice? Look for a server with several admins and a healthy mod team. Someone's more likely to burn out if they're a one-man band.)