Completely disagree with this, you handled yourself well and expressed yourself honestly and made an interesting PR case for yourself and your firm.

I'm inspired by how you stood up for yourself.

"a reputation as being troublesome loose cannons isn't a good way to grow market share."

They sent a DMCA notice that was ignored and are justified in being angry. Perhaps a reputation as someone worth copying who doesn't put up with bullshit is exactly the reputation they want vs. willing to roll over because we think we might make some money somehow, or want to win the approval of others.

There is a misconception that being "angry" is somehow a character flaw. We live in this world where everyone is pretending to be "happy" and we shame others for expressing anger.. Anger is a super healthy emotion and when acknowledged and not stuffed into your shadow it can help drive amazing progress.