The best part of the fediverse is that anyone can run their own server. The downside of this is that anyone can easily create hordes of fake accounts, as I will now demonstrate.
Fighting fake accounts is hard and most implementations do not currently have an effective way of filtering out fake accounts. I’m sure that the developers will step in if this becomes a bigger problem. Until then, remember that votes are just a number.
How would you prevent someone using wildcard domains from spamming servers the same way they can spam clients? The Fediverse has no way to distinguish between subdomains and normal domains. Anyone running an instance through classic DDNS would be affected by this.
The approach could work, but it would invalidate some major assumptions in the Fediverse itself. The algorithm would also need to make sure a few single user instances don’t get to sway entire servers.