"For some of my customers, the tiny friction-reliant spade connectors in their wiring would seize, or come loose, or fatigue and break after just a few trips."
That's not a spade connector. They call those bananas or bullet connectors in Finland, not sure about the rest of the world. Widely used in for example motorcycle electronics. To me those magnets just look an expensive solution to non-existing problem.
"For some of my customers, the tiny friction-reliant spade connectors in their wiring would seize, or come loose, or fatigue and break after just a few trips."