They are trying to build a tech stack for mass airiel surveillance.

Flexible, light, and high efficiency solar? Can be molded over a wing, not introduce too much weight, and capture every joule of energy available. Why not encourage cheaper, clunkier solar that gives you more energy return for the dollar? Because it wouldn't provide that application. Why not use solar capture to preheat water to reduce water heating costs, and thus avoiding the inefficiencies of generating electricity from it and the cost, or use it to heat homes directly? Again, it has no use to long duration drones.

Light-weight lithium-surfer batter cells? Why not use the gasoline that already works well for cars? Why not electrify the roads for actually far less cost than roads cost anyway (grading surfaces and maintaining and pouring asphalt is actually really expensive, more expensive than wire). Well, that wouldn't have a surveillance application.

Liquid hydrogen energy? Hydrogen isn't even good for the environment. To obtain it you have to burn electricity that needs power plants, which pollute. The same conundrum exists for electric vehicles, but obtaining electricity is a lot easier than hydrogen for most people and businesses. So why do we need it? Storing liquid hydrogen is a difficult problem that is expensive. Cars don't need that kind of expense when a tank that can hold a liquid at standard temperature and pressure will do, if you use gas. But hydrogen is light weight for it's power density and so it is a useful energy source for the more high power long duration flight (quad copters). We can already get 15 hours out of a hydrogen powered drone, and over 100 miles.

Carbon fiber. It's so light and strong. Why is light so important? The stuff isn't even economical enough to use in commercial airplanes and aluminum does the job just fine. Why does the consumer need to get excited about something that isn't even practical for the one industry you think would need something light? Because if you want max duration flight you need something with almost zero weight, damn the price.

5G. 5G is only good for when you have line of sight. That's no good for consumers. It doesn't fit our needs as consumers and we don't want to adjust to it. Thinking about where you are to use a cellphone is going backwards. If we want to be pinned down to a location and need speed, we have wifi for that. Why would we want 5G? Well, these planes can maintain line of sight with a tower and with each other. We need high bandwidth to transfer all the high resolution large area photography/video in real time. Keep in mind we need to keep power consumption low. Transcoding video to low bandwidth is probably not something a high duration flight drone should be doing. So we need raw 4K capable transmission, from line of sight, and need the infrastructure over the whole US. We can't get that out of 4G. Hey, maybe graphics cards and hardware accelerated transcoding are related too.