If requesting opinions, without government restriction Moore's law would probably apply. Quickly though, the government is going to restrict UAVs to "following designated roadways"... particularly when folks start sh00ting them when they fly over their property to steal the contents.

What scenario are you thinking about? We'll have more UAVs flying over time, but the time to double being short and staying consistent - I don't really see the specific reason to care about the rate of increase. My bet would be you see a combination of trends like how commercial air traffic expanded from the 50's to today, as well as like what happened with bird scooters (growth/death) turning into current ebike personal transport. So there will be cycles of businesses pushing, and communities/gov keeping it in check