Or picking between Gmail and Hotmail, or any other e-mail service. Livejournal or Blogger. It's no coincidence the examples I can think of seem slightly old hat, because these things have been out of fashion for a while. They need to involve the blockchain somehow if they want it to seem modern.
In any case, it does seem like a great platform and might blow up in time with few changes in the onboarding process
Yeah, the instance names are often quite silly, but there's silly people on there. I mean 3000 variations of "mastodonUKsocial.com" or something wouldn't really tell you all that much more. If you don't want to go to mastodon.social, the biggest english language instance, octodon.social is a good, smaller (~11k users) general instance with a good vibe. Fwiw i think a lot of people use twitter to follow 'their kind of people' (lgbt groups, open source fans, music people) and this codifies those groups a bit more into proper instances/servers/communities, while of course allowing you to follow other people.