I don't know you very well so I can't fully tell if you're a bastard yet, but, if you don't mind me saying, you often come across as very gruff and aggressive on people. If you act similar here on the forums and in real life, then, well, I would think you were a jerk. I'm assuming with you it's "What you see is what you get. Deal with it or bugger off". That's not necessarily a bad thing depending on what degree you hold to that. Being true to yourself is a good thing, but being inflexible to the people around you and unresponsive when you hurt someone shows a lack of respect. Even if it's "I didn't mean to hurt you like I did, but that's how I am" is better than "You think that. So be it. I'm not changing". The first statement didn't even have an apology in it. It's a tactful way to state your opinion without offending people.
I do think that unlocking Mr. Mustache's last locked post was ridiculous. It was a goofy post to commemorate his last lock, and calling it an abuse of power when it affected no one was silly on your part, I think. It was a kill-joy and tactless. I'm not a moderator so I don't know the rules, but if I WAS a mod and saw Mr. Mustache's last post locked like that in a thread all it's own, I'd give a smile and go on to moderating more important things. It was in the SPAM board, after all.