If you want to keep something in orbit around the Earth, you need it to be flying parallel to the surface at speeds exceeding those of bullets. Get high enough above atmospheric drag, and stuff will continue to orbit as long as the moon does.
The moon has been around for 4,530,000,000,000 years, give or take.
Humans have been throwing junk into space, and occassionally blowing orbiting crap into countless smithereens, for about fifty years. As a result, the risk of impact to large objects such as shuttles, observatories and space stations is one-in-a-few hundred.
Since it’s obvious that it’s a bad idea to fill the orbital environment with junk that’s damn near impossible to get rid of, why do we keep doing it?
Because every species operates in its own flawed self interest, I guess.