Agreed. If the spectrum had been treated like other property all along, owners would have a strong incentive to figure out how to carry more data.

Landowners have a similar incentive. And, where it makes sense to do so, we see buildings that are many stories high, effectively using the same land many times over for the same purpose.

But in spectrum, we have spectrum lying around unused, while emergency services can't even get usable spectrum to save your butt in an emergency. Its well known that cops and firefighters couldn't even be alerted to leave one of the towers.

And this problem has still not been solved. But they can buy land with no problem.