Dealing with space debris doesn't require individual action from hundreds of millions of people though. It requires the governments of eleven countries with orbital launch capabilities (counting the ESA as one) to work together.

11 Countries? The UN Security Council has five permanent members and they don't always work together (any one of the five can veto resolutions against its own exonomic interest).

The UN Security Council isn't meant to be a politically nimble engine for progressive economic change; it's meant to prevent a shooting war between those major powers. Judging the UNSC by the standard of that design intent and purpose, the UNSC has been quite effective, a few regional proxy wars could have been much worse for everybody on this planet. We can call it a failure if/when America and China start WW3 and cover everybody else in fallout, but that hasn't happened yet. So far, the United Nations Security Council is working well.

I'm not convinced that the latter is any easier than the former.

There was an unparalleled global knee-jerk and the sort of global coordinated economic reorganisation we've never seen before in the entirety of history. The politics of the situation are still roiling under tensions and stresses that haven't been seen in decades. A vaccine has been rolled out roughly a quarter of the worlds population in 18 months. Vastly more efforts are hurtling through the economic system as humanity reorients its social and technological bearings. Never before has there been such a bleak future for the humble coronavirus.

The situation is neither pro- nor anti- our ability to organise at a mass level. This has been a remarkable 2 years to be alive and we've seen a level of urgent response that has never been achieved before, ever. With 3 years to prepare, anything is possible for this Kessler business.