Why not just get together with other companies and work on an agreed-upon plug design they all use? Better still: Don’t make it proprietary. Let any manufacturer who wants to use that same plug system use it.
Behold: VW, Porsche, Audi, BMW, Volvo and let’s say Ford all agree upon one plug design they’ll all use and that any other manufacturer can use for free. You’re telling me that won’t have a good chance of becoming the standard?