Yes. Area doesn't consume energy, people do. Otherwise Russia would be the most eco-friendly country in the world, and something like Luxembourg should be considered an abject failure of environmental policy.
I am just stating that more pollution per square foot will destroy that part of earth more and therefore damage environment more. So objectively speaking you are correct, social issues aside, Luxembourg should be considered an abject failure of environmental policy. But the issue of pollution is complicated and involves social issues so my perspective is not very helpful when you make policy decisions or include fairness towards people, etc.
I am just stating that more pollution per square foot will destroy that part of earth more and therefore damage environment more.
CO2 does not care about which piece of land it gets emitted from: As far as the main subject under discussion goes (in contrast to, say, air quality), pollution per square foot is an utterly meaningless metric.
Some pollution impacts are felt locally (heavy metals), some regionally (acid rain from upwind sulphur oxides), and some globally. CO2 is one of the global ones. It's very well-mixed in the atmosphere.
If we could point to a plume of obviously-warmed land downwind of a city, it'd be a much easier sell to the layman.