Agreed in general, but debris from collisions can head upwards as well.
For example, Kosmos-1408 orbited at about 475km and left debris from 300-1100km. This is an older debris chart, but it shows that event in red.

Agreed in general, but debris from collisions can head upwards as well.
For example, Kosmos-1408 orbited at about 475km and left debris from 300-1100km. This is an older debris chart, but it shows that event in red.
