It’s…complicated.

On one end, a clear sign of “f*** you” with such decisions is important. On the other, Mozilla is already in a rough place, and with so many genuinely good projects, including Waterfox, depending on Firefox or at least Gecko, this is akin to biting the hand that feeds you.

All these teams cannot maintain their own browser engine, and without it, they may as well turn to dust. Thereby, maintaining their upstream is in their best interest.