Pretending these little moments do anything to help is not a liberal idea. It’s just as stupid as avoiding exercise and eating less to reduce your carbon dioxide output. It demonstrates a complete disconnect from the ability to contextualize real issues from things that actually help.
Stopping climate change is not a “liberal idea”, at least not in the mainstream liberal sense. Airplanes are still filled with liberals even quite far left on the spectrum in the US (even AOC flies all over the east coast because her time is “too important” to be disrupted by climate change).
Some do, but doing something stupid and patting yourself on the back is worse than doing nothing at all. At least someone who intentionally doesn’t do anything knows they aren’t doing something and might vote for real change.
In my experience, those that don't take any individual action rarely take any meaningful action on any other plane either. Either you get it and care, which means you do whatever little you can do yourself and work for changing the society, or you don't get it and you don't care.
Those that criticise individual action are most often the ones that can't bring themselves to sacrifice even the smallest pleasure or convenience, but still feel a small pang of guilt whenever they see other people doing their best to do their part.
Stopping climate change is not a “liberal idea”, at least not in the mainstream liberal sense. Airplanes are still filled with liberals even quite far left on the spectrum in the US (even AOC flies all over the east coast because her time is “too important” to be disrupted by climate change).