Can you give a rough estimate of what fraction of space waste is due to differing orbits of satelites? Like very low vs low vs geostationary? I don't know the gradations between those either.
The biggest issue is by far the 600km to 2000km altitude band. It is popular for both LEO and SunSync sats and is high enough above the atmosphere that minimal propellant is needed for orbit boosting.
GEO is more or less safe because it's unstable (dead stuff drifts outwards), well kept (slots are limited by the resolution of customers' terminals) and typically doesn't have high relative velocities.