We don’t know anyone would bother to make a malicious clone. Most likely some anarchist or liberal (heh) will buy it and do something silly like put an anti-ML screed or some NATO propaganda or something else simple there to “troll the tankies” so all this talk is a bit premature.

Also I wouldn’t count on all lemmy apps to necessarily cooperate. There have been other instances that have gone offline permanently for instance, is there any precedent to banning closed instances to prevent re-use? If not that would need to be discussed as an official suggested lemmy best practice. Otherwise the app devs, most of whom are probably not that sympathetic to places like that if not potentially outright hostile are unlikely to comply.

Personally I think you’re begging to open a whole can of worms proposing app-side site-bans. What’s to stop a liberal dev of a big lemmy mobile client from just adding “tankie” domains to prevent tankies from using their app? Once you plant the idea that it’s necessary to maintain a ban-list and do so, the temptation to abuse it is immediately there whereas right now it would be at least a little hassle.