The reality is that, for most people, there is absolutely no utility in following accounts on #threads let alone seeing posts from them.
But for those of us who have, for instance, a crocheting cousin who uses threads to promote their wares, then choosing to be on an instance which allows us to follow said cousin on threads doesn't cause any harm to the rest of the #fediverse, because people on instances who've blocked threads will never even see a re-post from threads, even if they follow me.