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So basically a small college football stadium's worth of people spread out over a surface area somewhere between Neptune's and Saturn's.
...albeit some of the people weigh 8 tons and move at the speed of 7km per second...

https://en.wikipedia.org/wiki/Envisat

7km/s is "standing still" in low-Earth orbit.
Not if you're moving in a different direction. The opposite one, for instance.
The amount of delta-V required to orbit opposite of Earth's rotation is immense and very few projects have wasted the resources on it. I think most collision concerns come from inclinations and changing orbital altitude due to atmospheric drag. These are predictable effects, but it gets dicey quickly if your surface area increases because your vessel explodes.
It's not as rare as you might think. All sun-synchronous orbits are slightly retrograde (inclination = 98 degrees or so at 600 km) in order to take advantage of the precession caused by the earth's equatorial bulge and maintain the same local solar time in the ground track.

Also, Israel always launches in a retrograde orbit, since they have neighbors to the east who would react too well to what looks for all intents and purposes like a missile launch, or to expended rocket stages dropped on their heads. For that reason, Israel launches retrograde over the Mediterranean.

Even neglecting a retrograde orbit, though, just a slight difference in inclination is enough to totally ruin your day. Even if you're only off by one degree, if you're travelling at 7.8 km/s your closing perpendicular velocity at the node crossing is 7800*sin(1 degree) = 136 m/s. That's almost 500 km/h, plenty fast enough to ruin your day.

Yea for sure.. I would hope that there is some rule now related to making sure things can be deorbited with some scheme relatively easily? For example a mandatory unit that attaches to the side of your satellite that has a small antenna only possible to communicate with using a high gain antenna on the ground that can transmit back using a battery that is only for that unit and can only command some relays to fire thrusters to de orbit the thing and read back basic telemetry to help validate what the slow down burn direction is.. anybody know how they accomplish this?
To deorbit a satellite, you need an antenna (to receive the command), electricity (working solar panel / battery), working on board computer, fuel, correct attitude determination. So basically you need a full working satellite. As soon as one of these element fails, your satellite is dead. At 10-20 k dollars per kg, you dont want to add another satellite to your already expensive satellite.

Concerning rules, there is some progress, because nobody wants a Kessler syndrome, too much is at stake. For instance, European satellites are launched only if they naturally deorbit in less than 25 years (for LEO, of course. Above a certain height, atmospheric drag is too weak).

Actually, the newly-proposed FCC rules would require fail-safe deorbit systems when operating above 550 km and below 2000 km. Above 550 km, most stuff takes more than 25 years to deorbit, and the NGSO volume below 2000 km is considered the most useful (and thus most likely to get crowded). These fail-safe systems should be designed to cause the satellite to deorbit within 25 years of activation.

https://docs.fcc.gov/public/attachments/FCC-18-159A1.pdf

The FCC hasn't proscribed exactly what these look like (that's implementation), but electrodynamic tethers would seem likely.