Sure, that's easy... I did not say that traditional energy sources had a zero footprint, they do have a footprint. But things like coal, oil, natural gas come from underground. Most of the refineries, processing facilities and power plants are already in place. Mining more coal or extracting more oil to generate power will not consume much more surface area of the planet (zero in the case of existing mines and wells). Any expansion of solar will consume more surface area and destroy vegetation (even in a desert), unless we get smarter and utilize the roofs of existing structures....
By ignoring existing infrastructure you are already starting off with a false equivalence. You have to count everything in order to have a far comparison. And that also includes the byproducts of those power stations.
Anyway, I have nothing against solar, but it's not as "green" as everyone seems to pretend it is. Any source of energy has a "cost" associated with it. Even if you covered every square inch of the planet in solar panels, you still couldn't generate enough power to meet demand. Solar is great, but it's not the end-all be-all solution for energy. We need to responsibly use multiple sources. Coal, oil, and gas are natural products, btw. Wind is nice too, unfortunately the big turbine blades are killing a lot of birds.
You say you have nothing against solar, but you used "green" as a pejorative and as an absolute. And this comment about "Even if you covered every square inch of the planet in solar panels" is totally wrong. These calculations are easily done and the total area needed is less than 0.5% of the earth for 100% solar power to meet all requirements.
And as for birds and wind turbines .. yes they killed, but how is that compared to the number of birds killed by flying into buildings? Does it represent a larger or smaller amount? So again, you can't just trot out an absolute and make a proclamation about it.