They have been. That's what I'm basing my arguments on.

You've been mentioning a ca. 70,000-bird limit. I think that comes from Bongers & Torres [1]. Their paper runs LEGEND (LEO-to-GEO Environment Debris Model). It does not distinguish between LEO and GEO. That's material because the natural decay period for an object in LEO is on the order of months to years, for LEO, to decades to centuries, for GEO.

Kessler in GEO? Real problem. If you wanted to be a space terrorist, you could probably engineer a cascade today that would make large sections of GEO unusuable for decades if not centuries. The point is that isn't possible for LEO, where you may make a mess in a few orbits for a few years at best.

> Quibbling isn't an argument

Sorry, wasn't quibbling. I genuinely couldn't tell what you meant by "highest level." (I was picturing a food chain, where big clouds of debris "eat" smaller satellites in their way.)

[1] https://www.sciencedirect.com/science/article/pii/S092180092...