Treaties meant to ensure sustainability in space don’t currently regulate private companies, and not every country has signed on to an agreement for sustainable space exploration.
You can filter here to show the SpaceX group, which is a whole bunch of Falcon 2nd stages. It isn’t like anyone else puts effort into to deorbit their 2nd stages, SpaceX just launches the most.
They also dump Dragon 2 trunks and used to dump some Starlink deployment hardware (which I think is now attached to the 2nd stages), but those two examples are in such low orbit that they don’t last long.
You can filter here to show the SpaceX group, which is a whole bunch of Falcon 2nd stages. It isn’t like anyone else puts effort into to deorbit their 2nd stages, SpaceX just launches the most.
https://sky.rogue.space/
They also dump Dragon 2 trunks and used to dump some Starlink deployment hardware (which I think is now attached to the 2nd stages), but those two examples are in such low orbit that they don’t last long.