Being an instance admin/mod is a position of responsibility and accountability. You owe (yes, owe) the people on your instance the assurance that your actions as a leader will be level-headed, fair, and free of personal grievances in your dealings with other instances—because your behavior with users outside of your instance gives great insight into your potential behavior inside of your instance as well.
I am begging everyone using the /#fediblock hashtag to keep it clear of personal vendettas and diatribes. It's your choice how to manage your community, but misusing fediblock, a tool for keeping Masto users and communities safe, for lashing out and revenge, flies in the face of a worthy goal and a powerful tool for good.