Most people won’t switch though, they won’t want to lose their username, their feed and so on, we’re creatures of habits…

You can keep your username, export and import your subscriptions and block list in two clicks from the settings.

Hell, trolls could go around and recreate accounts on the top 100 instances with the same username users have on other instances to prevent them from reusing the same username elsewhere, just that is a weird concept to explain “Oh yeah, someone else can create an account and pretend to be you and unless people notice that the instance they’re from isn’t the same, there’s no way to know it isn’t you!”

"You are bob@gmail.com, but someone could create bob@outlook.com and pretend to be you"

Also, this kind of impersonating would probably get the trolls banned.

You’re sending users to Lemmy.we but in the end it’s an instance controlled by one person paying the hosting fees and with the last word on what goes on on their server.

Lemm.ee had 5 admins. The main one has been very clear that he keeps defederation to a minimum: https://lemm.ee/post/35472386?scrollToComments=true

Of course you need to trust him and his team.

If you prefer a paid model where you have a customer relationship with the admin, you might to have a look at https://communick.com/services/lemmy/

The owner is @rglullis@communick.news , who commented below

Hell, trolls could go around and recreate accounts on the top 100 instances with the same username users have on other instances to prevent them from reusing the same username elsewhere, just that is a weird concept to explain

Yes but that doesn't mean you should get automatic dibs on a name everywhere. It's just a name. If you are Joe Bill at lemm.ee, that does not give you any rights over the name Joe Bill all across the world. Statistically speaking, there's at least 18 thousand other Joe Bills around at this very moment.

Like, this is something that is already solved by the instance's moderators.