[whoopdedo]

Another explanation[1] that shows how it's not just the cost of escaping Earth gravity (which is high enough already) but the delta-v required to de-orbit. It's easier to throw the garbage out of the solar system than it is to descend into the Sun.

[1] https://www.youtube.com/watch?v=LHvR1fRTW8g

[jessaustin]

It would be much less costly to just throw it all at Venus. b^)