Regardless, I think it’s a fair critique: buyer’s remorse is a real thing with Tesla. It’s one thing to buy a $3000 computer from Apple and have it replaced with a much better one the next week, it’s another to buy a $100K car and have a major improvement two weeks later.
Plus people but cars when then want cars, some will always lament they could have waited a bit, but most I expect will be happy to own a Tesla that was (and is) amazing just a few days ago.
If you want change in this regard, it's not going to come from Tesla.
For instance, let's say I pre-ordered a Model 3 now. But I won't get it the first half of 2019. And then a month later, Tesla announces Model 3 with Autopilot 2.5 hardware or whatever, holographic HUD, and so on. And that new car will ship within 2 months. Then I'd feel pretty screwed by Tesla...
In short, the delay between reservation and receiving the car is not an issue.
Big difference between buying a camera and buying a car.
For a young professional, buying a $35k car is probably just as eventful and significant to their savings/expenditure.
Tesla has done this for a long while. Newer larger battery pack options, newer interior and tech package options, and completely new performance and configuration options (insane, dual motor, and autopilot 1.0 all hit at once)
While there wern't announcements ahead of time what was coming, there were often advance notice that there was an announcement coming, and even when there wasn't - there was a big period of quiet from Tesla leading up to it.
For Autopilot 2.0 everyone knew it was coming for at least the Model 3 launch (Elon said as much at the Model 3 announcement), they just brought it forward.
It is really no different to what happens to customers for a bunch of other tech companies. Canon sure doesn't tell anyone when their new models are coming out - you know it'll probably happen at a major trade show, but only if you're someone that follows that kind of thing. The average customer at their camera shop isn't going to have the sales guy say "Hey, wait a week and we'll have the next version available."