Kratzkopf
The key is to do both because they are principally coupled and nothing happens as long as consumers and corporations just point at each other and use it as an excuse to keep on going like before.
Of course you are right that the focus should lie at changing CO2 output at the producer side because the influence is much more focused there. N my opinion it is also dangerous arguing that the companies only supply what the consumers want because that statement is based on the consumption and is biased too much by what the companies offer and at which price. Consumers usually socioeconomically do not have the choice to buy a product at 1.5 times the price, even if they would prefer it for environmental reasons while these companies have immense profits and can and must afford to reduce and finally stop emissions.
To add to your last two paragraphs: even if the elected parties enact the more environmentally friendly policies, many voters will be unsatisfied with that because they imagined a solution would pop up where they themselves would not be required to make sacrifices. I imagine memes like this could be a reason for that as they imply that corporations emit greenhouse gases totally decoupled from the people’s consumption. I fully demand that corporations take more actions to reduce emissions although it will lower their profits, but I also ask (mainly) the privileged people who live in the global north to accept necessary reductions in lifestyle and consumption as a necessary consequence.
Isn’t that basically why laws need to be put in place ensuring that these high emitting companies (which are mostly from the global north) reduce their carbon emissions? The circumstances are often consequnce of ongoing western exploitation and they will just get worse if nothing is changed because it is not the rich countries which will suffer most from climate change.