that will make some people immensely rich

Not sure what this means. Most satelites make everyone a little bit richer (weather, GPS, communication satelites).

it’s up to the cooperation of countries to research, mitigate, and control it

I would argue that companies SpaceX have a lot to lose from space debris. If space becomes inaccessible, they can’t do any business. They do a lot to mitigate space debris (especially with Starlink), and this is rational because too much space debris threatens their mission.