This marketing mix up is due to Tesla's naming scheme and Musk has taken responsibility for causing the issue. The very fact that they had to make that comparison web page would indicate that there must be a lot of people reading it and saying, "Wait, what? So that's what the model 3 is?" I bet a lot of those people placed deposits without knowing what they were buying. It's a fine example of Enviro/Tech bandwagonism.
Marketing mix up? Pretty much standard in the car industry IMHO. Look at Volvo line up, a T5 used to be a 5 cyl turbo, now it's a turbo 4, why not a T4?? If you slapa supercharger on top of the turbo, it becomes a T4S? No i't's a T6. And if you add plug in hybrid it must be T4S PHEV? No, of course not it's a T8..
I could go trough the Infiniti mess of model designations but I'm sure you've got the idea..
Yes, marketing mix up. Despite your contention that this is business as usual, the CEO of Tesla views it differently. Here is a quote from Elon Musk himself (you read the linked article, correct?):
"We're going to be a broken record on this front," Musk said earlier this month. "But we really have to be emphatic for an error that I, unfortunately, take full responsibility in naming something that inherently would cause confusion in marketing."
And yes, lots of brands have confusing model names. However, I've yet to see any that have had to produce a webpage explaining why a $35,000 car is different from a $100,000 car.