5G (or whatever "G") is not a technology per se. It's just a convenient banner providing a quick reference to the capabilities. The related radio access technology is more known as E-UTRA (and its derivatives). It'll be boring to dive deep into the details here (it's so huge topic) but technically, the difference between E-UTRA and the previous technology (UTRA) is very significant. Nothing in common, actually. E-UTRA is entirely different thing. It's much easy to learn and to implement, taking advantage of the computational capabilities in state of the art silicon chips. So it was a major clean-up from the engineer's perspective.
But the difference in RF spectrum usage efficiency between that two technologies is marginal. Both are good enough in that regard and both provides max. data throughput rate that is quite close to the theoretical maximum for given conditions. That's an important fact because it means that today, if you want more throughput, the only way to achieve that is to use more RF spectrum resources. You can't get noticeable gain by improving the technology itself (e.g. by inventing more efficient modulation schemes, using more advanced compression algorithms, designing better signaling protocols, and so on). The signal engineers are always happy to propose excellent technological improvements but that's simply because they are making their money from that. In fact, no additional spectrum allowance, no progress in the industry. So new wave of the spectrum wars.
I think that this particular issue will be sorted out very soon. Because it's not only the aviation community that's very upset by the new spectrum allocation, but the other corporations too. E.g. the GNSS guys are also among them, and I presume the military will also add their increasing weight to the push. So we will win the battle, no doubt. But I'm afraid we can't win the war in that way. Because if someone wants a resource very badly, he will keep trying to grab it. So he will keep trying to overturn a court decisions, to lobby for regulation changes, etc. After all, governments are elected by the business. No one will be happy, except the lawyers. It's a system problem.
Perhaps it'll be better, instead of trying to break the system, to find a ways to use it to our advantage. For instance, to set up a non-profit troll company, you can call it United Taxpayers Corporation, because each member of the club voluntarily taxes himself as much as he can to raise enough money to make a winning bid for the spectrum band on the auction. When the band is lawfully obtained, the company can install there a machine guns controlled by the image recognition software to prevent any human activity. Of course, it will not be a one time payment. Operational expenses, policing the band, providing enough physical security for the board members, guarding them against the criminals hired by the businessmen (they sure will), this all will bleed money constantly.
Seriously, widespread use of the troll company concept can cause to dramatic change in public behavioral pattern. You're paying not to get the thing but for the right to not have it. Too many useless things are out there. No wonder more and more people are starting to think how to prevent the others from making the things for profit. Clear example of missed opportunity is 4K TV (let 8K alone). Some clever guys learned how to pack excessive amount of pixels in square millimeter and wanted to make money from that. I was surprised on how welcomed it was by the public. Even with the special test images, the visual difference between 2K and 4K resolutions is barely noticeable on a screens of usual room TV size. While a 4K content requires noticeable more storage, bandwidth and eventually electricity and raw materials. So it's in fact inferior to 2K because the former is much less efficient. Now the same sort of guys are pushing for 5G to faster transmit that stuff to the tiny screens of mobile phones. Just insane. Something needs to be done to stop them. Different times, different priorities. Less is now more, etc. Welcome to the boring new world, gentlemen