Comment by Sanzig

Not at all, it can be handled via international treaty. Frequency allocations for civilian satellites are already handled this way, a UN body (the ITU Radiocommunication bureau in Geneva) acts as a neutral party that handles satellite spectrum coordination between UN member states.

The ITU has no enforcement power, but fundamentally that doesn't really matter much, since enforcement is handled by the member states. Are there attempts by various member states to skirt around the rules or favour their own national interests? Of course, and sometimes these are successful - but nobody just outright ignores the rules, because they know it very quickly leads to a tragedy of the commons.

Administering an orbital LVT is exactly the kind of thing that could slot cleanly into an expanded ITU mandate. Where the money goes would be up for debate, but I think the cleanest solution would be ITU rebates most of it back to the government of the country that applied for the orbital slot provided that they demonstrate it's going into a space sustainability fund.

Is it perfect? No, but it's based on a rickety-but-mostly-works international model and it doesn't require global government conspiracy theories to come to fruition.