Geostationary satellites are way too far and few in between to meaningfully present a problem. The majority of dangerous (in Kessler syndrome sense) junk is on higher LEO and eccentric orbits.
Correct. Most non-Starlink constellations LEO are going up around 800 - 1200 km altitudes. Those orbits have century to millenium level deorbit times and pose significant Kessler risk.
