Each child born produces as much CO2 as 71 people going vegan for life. That ignores all the other ways humans pollute. Given that 130M babies are born each year, even if the entire planet went vegan right now (forever), it would only offset the next 324 days. If you care about the environment at all, you would focus all of your ire on the the real danger: countries with high birth rates.
However I suspect this has nothing to do with the environment for you. There is a duplicitous tactic employed by vegans which seeks to hijack the environmental movement for moral aims. People such as yourself have a moral problem with eating meat, and you know that many others care about the environment, so you attempt to wed the two. I am of course happy to be proven wrong.
I hope these comments make it clear to you that there’s never any off ramp for the “eat the rich” ideology. Once they’ve eaten the very rich, they go after the next cohort, and the next. It’s about pulling everyone down to the lowest level. We have repeatedly demonstrated this many times in many countries over the last century. It always ends in many deaths and fascism. The solution to that is free association, free commerce, and democracy. Individual liberty has plenty of drawbacks, but it’s far better than all of the alternatives we have tried.