We should be approaching the problem from all avenues, so I agree. But this campaign that ordinary people shouldn't arsed to do anything because it won't make a difference is absurd.
I can't be arsed to do it, not because it won't make a difference, but because I have no ability to know that an alleged lower-carbon product is actually lower-carbon, and not just marketing bullshit and accounting trickery.
Encoding it in cost is the only metric that the manufacturer won't be able to game.
It's the only honest, guaranteed signal for any product. Making purchasing decisions based on it is the whole point of market economies.
Tax carbon at the same cost as it takes to pull it out of the air[1], and consumers will start buying low-carbon alternatives.
[1] You should also probably take that money, and actually pull it out of the air, though.
As long as producers aren't taxed for emissions, consumers can't pick lower-emission producers.