TL;DR: The current Mastodon-signup is only removing the confusion of users on first glance, because it either hides the server-choice altogether, or leaves them with a choice that is impossible to make at this point of their Mastodon-journey. Instead, it should introduce them to decentrality on a lower scale, with a handful of handpicked servers to choose from, such that the decision makes sense to them and shows them the merits and fun of the concept instead of scaring them away. Ideal would be to give them a sense of agency. Then, chances are higher that they consider migrating again in the future and eventually internalize it as a permanent option of the digital world.
I’m not them but -
Forum style posts == reddit.
Short text style posts == twitter.
Just because lemmy is a forum style alternative to Reddit does not mean we should call it a reddit-like.
Just because mastodon is a short text style post alternative to Twitter does not mean we should call it a twitter-like.
It would be like saying reddit is a gameFAQs-like, but for more than just games. Is it inaccurate? Not exactly, but they are their own things. Related/inspired from each other, but so is basically everything that exists from art to practicality.
I think in this case, yes Lemmy was made as an alternative to the forum-image style posting that Reddit is now known for. However, lemmy and mastodon are far beyond that now too due to how it interfaces with ActivityPub (each instance being able to have its own community of the same name). It’s created enough separation that it almost seems inaccurate now to entirely call these a “-like” alternative.