This seems necessary and desirable, but pretty much a government function. I can't see how simple good-faith cooperation prevents abuse.

Possible abuses:

(1) Use the information to actually interfere or collide with satellites

(2) Use the information to track secret satellites by excluding traces from non-secret ones

(3) Free riders gaining secondary access without providing data

(4) Use access to this when traffic is more contended to enforce hegemony

(5) Anti-competitive coordination under the rubric of cooperation

And while the system might be helpful under ordinary peacetime conditions, will it make a war more or less destructive?

It's silly that NASA is planning for Mars and the moon but hasn't already solved this coordination problem on a world scale.