Seems like controlled landings on the belly with the help of airport fire fighting crews tend to work though.

I assume this is made possible by explicit system (aircraft + airport) design decisions agreed upon 50+ years ago.

Is that supposed to be a joke? The risk of a disastrous midair collision in that scenario is far worse than the risk of a gear-up landing.

How about a drone system that IS the wheels.

Great idea!

And if needed, to actually swap defective landing gear parts to whatever extent possible. Maybe difficult or impossible with current aircraft designs, but maybe future ones could be designed with this backup option. Maybe a secondary landing gear insertion point or something.