Not all instances are going to be equal in terms of things like stability and uptime. It’s going to be unfair and frustrating to users who might randomly end up on a bad instance. It might work if it only chose along the top x instances or something, to ensure a bit of reliability for new users.

Historically, it’s been known for its security issues and vulnerabilitities.

It was less about intangible “concerns” and more that most of their time spent moderating was from users of this instance and since they’re strained on time, it made sense to simply defederate until the necessary mod tools exist to make things easier.