On the contrary, the rational way of solving a complex problem that cannot be addressed entirely is to break it down into smaller ones, estimate their individual cost/impact/risk and start with the most cost-effective options.

In fact, people who actively shame others for eating meat, having vacations, and raising kids, are doing exactly that. Except, instead of optimizing the ecological impact, they optimize their own emotional return through gaining influence over others, similar to religious missionaries.

I think, for everyone who actually wants to solve the climate change problem, being honest about their goals could be a good starting point.