The moment Musk made the call on Starlink, he made all the other ambitions of SpaceX conditional on it. If Starlink succeeds, they can fund Mars colonization out of petty cash.
Comcast access + tv is essentially a US only business. They have something like 26 million access subscribers and 22 million cable tv subscribers. The access business alone is good for $25-$30 billion per year in sales. They've accomplished that scale just in the US market. A bunch of medium income and developed nations still have relatively slow Internet access, including France and Australia. There are an easy ten million Starlink customers waiting just in the giant US market.
Starlink will never fund a Mars colony out of petty cash though. It'll take nearly every dollar of profit the business generates to establish a Mars colony.
edit: what I was going for is, you can't take that number and extrapolate it to the whole world
Apparently the average phone bill is 80USD/month. Again some of the highest in the world. https://www.moneysavingpro.com/cell-phone-plans/comparing-us...
I would be interested in reading about the economics of this. Can you point to such an article?