I think that the "Mastodon is hard" vibe comes largely from folks who expect to be able to "find everyone on one app". I think when we tell folks leaving Twitter/Bluesky/Facebook/whatever about the Fediverse, it's important to address this disconnect with honesty and patience.
No, it is not "just like email". Because for 90% of folks email is "just another app".
It's more like webrings.