They’re in such a low orbit that they’re barely staying in space already. You could explode all Starlink satellites right now and all their debris would naturally fall back into the atmosphere and leave the orbit clean in just a few years at most.
Xiaomi bootloaders used to work like that. You’d have to jump through some bullshit hoops to register your phone for bootloader unlocking, and then wait a few days to finally be able to unlock it. Then they made that worse and worse, and afaik it’s so insanely difficult and inconvenient right now that it’s practically impossible to unlock your Xiaomi phone’s bootloader. This applies to all the brands under that umbrella.
I am about 97.37% sure Google will do the same over time and at some point you just won’t be able to install any APKs.
It’s not easier to that on the ground. Those analyses are done by large radars slapped on top of satellites. They can scan huge tracts of land in very quickly with very high precision. More precise than airborne systems. They work regardless of the weather. The same satellites can keep track of river flows, forest growths, volcanic and tectonic activity, floods, structures like bridges, whole bunch of things. They can be used for extremely accurate mapping. They are insanely useful tools.