Why aren’t they just de-orbited? It would take a lot less fuel to put them over the ocean to burn up.
It would take a lot more fuel to slow the satellite enough to deorbit, and in doing so it will also have to go through lower orbits on its way down. Orbits that things like GPS satellites and space stations occupy. So you not only need fuel to slow the satellite sufficiently to get it entirely out of orbit, you need enough fuel to maneouver it on the way down to avoid other collisions.