Reddit had ways to automatically catch people trying to manipulate votes though, at least the obvious ones. A friend of mine posted a reddit link for everyone to upvote on our group and got temporarily suspended for vote manipulation like an hour later. I don’t know if something like that can be implemented in the Fediverse but some people on github suggested a way for instances to share to other instances how trusted/distrusted a user or instance is.
Worth noting if you’re serious about Flash emulation, check out Flashpoint Archive. They have ways to play almost every single flash game and animation out there through a convenient launcher.