So when you say that the majority of communications takes place below 10 miles -- if you mean wireless, you're wrong.
No, I am not.
So then do you deny that there are very roughly a billion satellite TV dishes receiving signals from transmitters that are above 10 miles AMSL? (Above Mean Sea Level)
Nearly all communications originates and is received at a point below 10 miles in altitude.
Except the one billion satellite TV customers, who are receiving a signal from above 10 miles? Or are you slicing a technicality maneuver and saying that even though there are a billion consumers each receiving those transmissions, they are only transmitted from a handful of satellites?
Or are you saying that the data transmitted from satellites originates from below 10 miles before being retransmitted from above 10 miles and therefore doesn't count?
The only reason hop points exist is to maintain signal strength and reliability.
It has nothing to do with the mythological globe earth.
But a bigger dish antenna and a more powerful transmitter can also increase signal strength and reliability at a fraction of the cost of putting an intermediate hop.
Remember, to have an intermediate hop, you gotta buy/lease the land, maybe cut a road to a mountain top, maybe even run power up there, as well in most countries as licensing another radio site. Much much more expensive than just using bigger dishes and more powerful transmitters!
But seriously, if you really think radio link engineers don't use earth curve in their link distances (rightly or wrongly) then just find me a link that's farther than the curved earth math allows.
The fact that they don't use longer links doesn't mean the earth is curved, it just means they believe it's curved and they are just going by what they learned in school without questioning it.
My argument here isn't that the earth is curved because radio link engineers believe the earth is curved, only that their practice of putting up radio links is hindered due to their false belief in a curved earth. In other words, if they knew the truth and knew it was flat, they could do longer links for cheaper!
But if you think I'm wrong, then find me a single-hop microwave link (or a single segment of one) where the radio path would cut through the earth if the earth was curved.
I will check into it and if it checks out to my satisfaction I'll happily admit that at least one radio engineer ignored the round earth belief. You said I'm wrong, so please show me. Fair enough?