It takes real conviction to literally dedicate your life to projects like this, and RMS has that to spare.
He's not insane, he is just the opposite of politically correct, and while that can be charming in a person that is not the perceived spokesperson of a large community when you are you'd do well to moderate your language.
If you don't it costs because it gives your opponents plenty of opportunity to claim the moral high ground.
The funny thing here is that if RMS really wishes to see closed source vs open source as a battlefield then his way of going about waging the war aids the enemy by giving them a couple of really good opportunities to get him bad PR.
I don't think that's smart.
There's something comforting about Stallman's intransigence. Win or lose, Stallman will never give up. He'll be the stubbornest mule on the farm until the day he dies. Call it fixity of purpose, or just plain cussedness, his single-minded commitment and brutal honesty are refreshing in a world of spin-meisters and multimillion-dollar marketing campaigns.
—Leonard, Andrew, Salon.com
And I find name-calling and posturing to be in conflict with 'brutal honesty'.
(I'm firmly in the "This man is completely insane" camp).