Regarding sharing of the superchargers - it is a great development for many reasons. Among other(some have been mentioned):
- Great Tesla PR to the target audience. They may have bought a ID4 now, but the constant Tesla app PR, and the knowledge they only have access to part of the network will easily lead to the next purchase to be a Tesla.
- Charging patterns of individual car types can give Tesla probably very valuable information of non-Tesla car types - their usage, ranges, habits, etc. This could lead to focus of showroom centers in particular locations, perhaps even individualized adds on the Tesla app for these users for purchase of Tesla cars.
- It disentivises any other company making their own network, handing to Tesla an effective monopoly on the charging network. More great PR, more large profit form outside Tesla.
- Having a monopoly on the charging network would make the creation of a Tesla food chain at chargers very profitable indeed. This has been hinted, and I would not be surprised if it happens in a few years, perhaps with TeslaBots as waiters. This would also be a great advertisement and practical demonstration for TeslaBots - think how great the Boring company is a great advertisement for Teslas.