Yes, however I’m talking about a post that originates on Kbin being boosted on Threads. A big account can put a post in front of millions of people that can re-boost it and drive it up the charts. You’re right though: the solution is to block that instance :)
Sorting by new is similar to reading the federated feed in Mastodon. You can do that if you like, but you’re removing all collective and social control over what you see. To me, that’s a huge tradeoff.