Just a guess. I have no idea how to make a mortar shell nor how to aim it accurately. For a drone I just tape some explosives to it and then fly it remotely via camera to the exact thing I want to blow up. I probably don't know enough about it but it seems like something I could do right now. Just go down to the local electronics or camera store, buy a drone. Not sure where I get the explosives.
Flying it via camera is very limiting, you have to be close enough.
However it's quite possible and indeed not that hard to build a long range, autonomous RC plane. You just need to use the sensors typically found in any smartphone: GPS, camera (for ground imaging), accelerometer, magnetometer and so on, add inexpensive barometers and ultrasound or optical sensors for altitude, and mix all that up with the proper algorithms to end up with really accurate positioning. In fact you can even have accurate positioning when losing GPS.
If you're not concerned about speed, a simple and cheap powered model sailplane made of styrofoam could easily be made to fly for hours on battery. Cost: a few hundred dollars worth of parts.
From a pro-authoriatairian POV they're worse because the powers that be aren't seriously trying to keep them out of the hands of the commoners. The powers that be aren't doing that because nobody there are serious economic arguments against doing so and the danger to them is currently hypothetical. There's perceived risk that someday drones might someday help the BadGuys(TM) force a concession or topple a government.
Frankly, I don't see the big deal. The more asymmetric weapons systems and warfare techniques proliferate the more reason people have to be on good terms with each other. It's harder to bully people who can drone you or hack your power plant.