Labeling this as "cope" is just straight slander against vegetarianism. Most people who are vegetarian don't expect "it's going to change the world" so there's no "coping" to be had with the fact that it's not.

Vegetarianism choices can be based in health, ethics, not wanting to support mega corps, dislike of the taste, environmental impact, among other things. "it's going to save us from climate change in light of everything else going on in the world" is a tiny clueless subset of just ONE of those rationales.

Vegeterianism isn't "hopeless" or "cope" unless you're delusional enough to believe that everyone doing so would instantly solve our problems. Sure, some people think if everyone did it, it would make a difference, but very few think it'd fix all our problems.