- "And even at GEO, there could be a debris cloud as well causing issues, at least until the sun and moon gravity perturbs it enough."
Not a satellite expert, but I understand GEO clears out relatively fast (~decades), because of those 3-body perturbations,
https://www.agi.com/blog/2020/07/geo-satellites-don-t-decay-...
Your link talks about how this is an unexpected result, and only occurs at specific inclinations.
It's new information to me, though. Thank you.