Alien.top’s raison-d’etre is to create bots and repost things from Reddit.
The instance makes a bot with the same username as the poster from reddit, then makes a bot with the same username as all the commenters, and re-posts each comment.
Every alien.top user in this thread is a bot.
https://lemmy.ca/post/10599153?scrollToComments=true
I did a quick check, and it looks like 138 of the comments are bots.
Yes, you can. Defederate youself from Alien.top by migrating onto a forum. And stay there.