It is the same law, https://en.wikipedia.org/wiki/Federal_Aviation_Regulations

But drones are classified differently and the rules need to be updated and tightened up, particularly drones for commercial purposes.

I agree with you that FAR covers all airspace. There's an interesting case on airspace (over an Indian reservation) & an emergency landing that's winding its way through the courts right now [0]

[0] https://avweb.com/aviation-news/aviation-law/aopa-asks-feds-...