You are forgetting the anniversary matches in Uruguay, Argentina, and Paraguay.
Spain, Portugal and Morocco may be close, but it's still more air travel than is necessary as opposed to hosting it in one country. USA, Canada and Mexico is definitely worse than SPM, but yeah. It really shouldn't be about, "eh, it's not that much". We should really be doing everything we can to try and reduce it.
It's like with UEFA. When they introduced a Conference League, they got asked the question about environmental impact from more travel. Their response was, "not out problem, up to the clubs to figure it out". It's piss poor. How many more dramatic weather events do we need.