Purely anecdotal, and not to be used for investment decisions, but kind of interesting! Locally our upmarket so called "farm shop" are Tesla devotees and now have a row of 8 or so (mostly empty) Tesla charging points, mostly used by the owners I think. But a few miles down the road a hotel has recently opened and they are providing Porsche charging points for their customers.
Tesla don't have a clean run, though they are clearly ahead in the performance market for now. But you have to ask how long propriety charging systems can last. If electric really is the future that is a massive hindrance to it.
Yes, and Tesla have offered the IP to their charging system for free and as far as I can tell most (all?) other makers have not taken up the offer.
The deployment of new tech often follows similar lines of incompatibility and those incompatibilities can endure, e.g. almost nothing that fits a Ford will also fit a Vauxhall, one of the few commonalities is the fuel.
Given how relatively easy it is for anyone ordinarily skilled in the art of electric power supply to alter voltage and current it is likely that convertors will be created that will allow most power supplies to fit most cars, but in the by and by likely a standard such as the 13 amp plug will probably emerge.