Tesla as far as I know didn't publish a definition of the standard and the protocol. Without that I don't know how other manufactures would adopt it.
A comprehensive approach would have been to create a standard for the charger, plus open source implementation of both the car and the charger software, including the software for automated payment. Also libraries for phones abs to integrate (or for others to integrate with the Tesla app).
Establish a conference for charger testing, these exist for the CCS standard. Maybe even a certification program.
They could have made home charger and the destination charger just work with any cars. And then made deals with specific auto makers for access to Superchargers. Or have program where they allow access at extra cost.
> Perhaps they were worried about the quality and safety of others producing a subpar equivalent/variant that might have led to incidents that tarnish Tesla's name and reputation?
Maybe.
If you want my opinion. Its simply not how Musk thinks, thinking in terms of Open Standards and Open Source or even Partnerships just isn't an Musk thing Musk does. And everybody else is to busy doing what Musk wants to do. I think it one of the biggest weaknesses in Musk
Maintaining a standard, having open software and partners and so on, is management effort Tesla just isn't interested in it seems to me.