But this would be their 4th car. Tesla has been in the car industry for 13 years, building brand awareness.
Additionally, a lot of the people still buy Teslas with the motivation of saving the environment and abandoning fossil fuels. Where as hopefully Apple would just make an all around superior car.
This. Apple is already a luxury brand and has the money to make what Tesla cannot: a truly no-compromise electric car. Teslas, while perhaps faster than traditional ICE vehicles, have comparably less luxurious interiors. Additionally, Apple has such brand power that they could release a car tomorrow and have a guaranteed level of sales. Few companies would have the cash, expertise and brand value to develop such a product.
One item I believe that is missing from this obersavation is that modern design is all about getting the user to trust and love the product. In reality users should treat their products with more respect than trust, especially when considering privacy and security concerns. Even if something is useful, that does not mean it should be trusted.
An isomorphism between two graphs indicates that bijection exists between two graphs, or that there exists a method to permute one graph's vertices so that they are equal to another one.
What Merlin is saying to Arthur is that no matter what kind of graph K Arthur comes up with, it cannot be congruent to both G and H, or, that there exists no method to create a graph that is both G and H.
Lastly it is zero-knowledge because Arthur learns nothing of the relation between G and H, only that the K he computes is not both of them simultaneously.