The thing is that some of these people can be obsessive and probably have checked on their names more often than we sssume but you're right - it could be that they've been taken by other users, it's just weird that people noticed so many names moved around at the same time that this Lexa thing happened. Even Lexa being taken recently is already exciting enough, maybe TNT is testing stuff?
But I'm also just really eager for a purge so idk lol. I do hope they give us those extra pet slots beforehand though.