And that gives him the right to be a bully? To say he'd like to cut off a Thunderbird developers hands so he can't program any more? To call developers simians? Nothing gives anyone the right to come into Mozilla's Bugzilla and behave like that.

Simians include all old world monkeys and apes, including humans. While you might interpret it as being an insult, and it may have been meant as such, it is factually correct.