I think this guy does a much better job of critiqueing Mastodon than the article linked in the parent post.
https://hackernoon.com/mastodon-is-dead-in-the-water-888c10e...
Key points:
“The foremost problem is that federation is a lie. Well, it’s partially a lie. The benefits described above do work; if you send a message to anyone at @username@custom.website, it will be delivered to them. But if @custom.website is a domain that mastodon.social deems inappropriate, replies from that users on that domain don’t show up in your notifications or on your feed, unless you explicitly follow them. So if you’re having a conversation with your friend, @person@custom.website, and another user from custom.website wants to chime in, they will be invisible to you.”
And
“Suppose you’re a semi-famous content publisher. You have 10,000 followers on Twitter, whom you converse with regularly and have a large history of communications with. If you decide to switch networks to something like Mastodon, you immediately come into contact with the Hardest Problem of Identity on the Internet, which is that your social graph is not portable between platforms.”
I feel these are two very important limitations to understand about Mastodon.
I see Mastodon as basically Wordpress for people who want a twitter like experience off of twitter. Aka niche communities.