Zero responsibility for doing my research and coming up to a different conclusion than you? Oh hell no. I take 100% responsibility for it. I live it. I breathe it. I know more about the environmental impact of meat than 9 out of every 10 vegans I end up dealing with on the internet.
The 10th is either not a jerk to me, or is clearly a zealot. I allow for zealotry (not happily). I'm not a fan of willful ignorance.