Coming from CoH2, I cannot fathom why paradropped units are invulnerable until after they land?

It doesn't seem like very good design to allow paradropped units to be invulnerable the entire time they are parachuting down until several seconds after they land.

It seems to encourage very cheesy tactics, especially in large team games, where units are paradropped into the Fog of War just to give vision for 20 seconds uninterrupted so they can call in bombing runs.

Or a Fallschirmpioneer dropping on top of a machine gun to drop a Satchel Charge that can't be prevented in any way.

Or having to watch a Fallschirmjäger drop onto your support unit behind your lines, and knowing that you will eventually lose the fight and the point unless you reallocate units from your front line.

The tactical burden of paradropping units should be on the person calling them in, not on the person having to react to it knowing they won't be able to interact with the unit for another 10-15 seconds of down time.

Correct me if I'm wrong, but I'm pretty sure in CoH2 a unit paradropping in would be shot at by everything nearby (including mounted machine guns on vehicles) and the models would be extremely vulnerable. Can someone please explain how this wasn't a better design choice both in terms of game balance and realism?