Sounds more like he was scammed by the dealer than a Tesla problem.
That's not smart infrastructure, that's dumb infrastructure.
Even if Tesla is the only one doing this right now, I'm sure it'll be a thing in the future with other manufacturers and a proliferation of 3rd party repairs.
I wasn't even aware that it was possible for a car to be banned from the supercharger network. Sure, it makes sense in hindsight, but I wouldn't necessarily expect a used car dealer to know anything about this either.