Balance is relative. There will always be a “Top current”. You don’t nerf something for the sake of nerfing it or because it is stronger than the weakest of the bunch.
Bysmiel and Beastcaller are both strong, yes. But are you implying that they shouldn’t be?
Both take 6+ mins in the Crucible and that is when built for Cruci. Compare that to the fastest non pet builds and you will see nothing OP about it.
Sure, Pet builds can do higher SR shards. But those builds are focused on defense to the extent that they will be much slower than otherwise for all content. And higher SR shards are only for bragging rights and the challenge since the new Waystones disable loot. I see no imbalance or need for nerfs here.
Superbosses? Sure they can kill all of them. But even if you build for it, you aren’t killing Callagadra in less than 10 mins while the current record for Cally kill is 1:24 with a Retaliation build.
Also the current record setter for both SR and Crucible with Pets is the Ghol Set, not Beastcaller or Trinkets.