Those are among the worst, yes, but even the existence of subs like gonewild can have the effect of repelling potential users, especially those who don’t have an understanding of how the site is organized.

They read an article that talks about a sub for content they find objectionable, and from that point on, Reddit is “that site for (insert content they dislike here)”.

Much the same, I’m concerned that Lemmy will be known among those users as “that site for communists that support the CCP”.

Exactly.

It’s analogous to the way that Reddit knowingly allowing some subs to exist repelled some users.

Most were able to get past it and simply not subscribe to subs they found objectionable, but I’m sure many people just stayed away once they learned that certain subs existed and were very much known about by Reddit admins.

One key difference here is the way that your instance is able to enforce rules and to some extent influence and filter your user experience, and that’s worth consideration too.

I’m also curious if and how an instance like lemmy.ml can, for example, delete comments, ban users, take down content in cases of cross-instance interaction. Could the admins of lemmy.ml, for example, ban a user from another instance from Lemmy completely? From their local communities? Could they remove that person’s comments? Can they prevent their own users from seeing content they don’t like on other instances? Can they moderate content from their users that is posted to communities on other instances?