Drone swarms are seen as a more cost efficient way of gathering intel than one or two larger ones. Not all the drones reported are cheap according to some reports and may have been perceived as UFOs by civilians.

I take the point about satellites. That is completely valid. However, one thing military industrial complexes are good at is creating jobs and gobbling up money. Russia's is no different from the west's in that regard.

There is evidence China does this too.