Instance selection at sign-up remains the primary barrier to entry.
I think there needs to be a quick question form upon sign-up, going over the biggest differences between instances. Such as: "do you want downvotes activated? Do you want to see NSFW? Do you want little, some, or heavy automated blocking of potentially objectionable material?" etc, then have the sign-up page provide you with up to three instance options based on your selected preferences.
Otherwise you're either forcing users to do this research on their own ("ew, homework just to sign up for social media? no thanks") or they're going in blind and selecting at random, very likely ending up on an instance with qualities/features they don't like.
A separate issue: during the big 2023 rexit (when I moved over), the primary instance that most new users joined, lemmy.world, was a buggy, buggy mess, practically unusable for the first few days. I don't know if that was specifically because of the influx of new users or if it just worsened problems that had skated by when there were only a handful of users before, but I imagine that turned away quite a few potential new Lemmings. Hopefully that won't be an issue this time around, but I guess that depends on how big the exodus is and how much Lemmy infra has strengthened in the 2.5 years since.
