I actually think yanbu. And I do eat some meat and dairy, although not a lot these days. I am a former vegan and was veggie most of my childhood. First went vegan in 2003 (before it was cool
).
I think that, if someone really cares a lot about the planet, as you clearly do, they should do as you do; forgo meat, dairy, having children, driving a car etc. Equally, if someone says they really care about animals, they should be vegan.
Having said that, I don't care as much as you do.
I care enough to adjust my life as far as I can, but for me, there is a balance to be struck between enjoying a healthy, happy life and also minimising damage to the planet.
But, if someone truly cares enough and is selfless enough, they should be doing what you do.
There is an alternative to everything, but I've been vegan and I definitely prefer not to eat the substitute meats, cheese etc, I'd just rather eat a small quantity of meat and cheese. I never eat beef, fish or lamb and I avoid butter and cheese as these are the worst offenders for the planet. This has reduced my carbon footprint.
I have children, but that's sort of a done deal - they are here. What would antinatalists have me do? Kill them?
Also, there is no direct correlation between what I do now and how I will fare as CC worsens. I'm as interested in preserving myself, my family and my community and making our lives as bearable as possible as things get tougher, as I am reducing my carbon footprint. They aren't exactly the same thing.