It will take tesla a while to reach world dominance, as i expect it to do. it will take a lot longer for the tesla to get there, however, than it did apple because of the capital/time/supplier resources needed to grow. at the same time, however, i don't think that tesla will be unseated from the top as quickly as some say apple was because of the same reasons.
if another car company comes out with superior EV technology (which i don't see in the foreseaable future), i think this still helps tesla. it just hurts ICE manufacturers more.
people have made the claim that tesla is a technology company more than a car company. i disagree. it is fundamentally a car company and its evolution will reflect that. it might also be an energy storage company, but we still have to see how that plays out.