My biggest gripe with hearing about fully autonomous cars is northern climates and their inability to handle bad weather.
There's a mostly straight street on my very ordinary and safe commute home. When it's raining at night and the road is wet and reflecting street lights, it's actually very difficult to see the lane markings and make sure you're sticking to your lane. And in those conditions, it's not always safe to be constantly checking your blind spot for a car beside you. This is in an urban environment, no snow, no crests or crazy curves, no risk of fallen trees, and I find that a stressful drive despite having driven that road thousands of times.
My biggest gripe about hearing about the invention of the automobile is the lack of mechanics and gas stations.
My biggest gripe about hearing about the invention of the internet is the lack of home computer ownership.
etc. etc.
As an historic note with little relevance to your point, this wasn't solved until the US entered the second world war and the government built a bunch of them for heavy bombers, which were later converted into civilian use.
That's why the flying boats, like the Boeing 314 Clipper, were the go-to plane for long distance travel pre-war. There's no need for a runway when you can land and take off on water.
"lack of mechanics"
This isn't really true. The early cars could be fixed by most any mechanic or blacksmith. Remember, farm equipment was already pretty mechanically complicated.
The lack of gas stations was much more critical.
The point is that you must give new technology time to grow and become mainstream before you can expect them to be everything for everyone.
Lots of new tech will never be everything for everyone
At best, treat it as comment about how hard it is to think what detractors to X might have said before X became wide-spread. I believe your example of 'lack of mechanics' is poorly chosen; akin to saying 'My biggest gripe with hearing about fully autonomous cars is that they will be so expensive that only the five richest kings of Europe would own them.'
As a real-world examples I think are better, 'My biggest gripe with hearing about telephony is there won't be enough operators to handle the number of calls.' 'My biggest gripe with hearing about computers is that they are too bulky.' 'My biggest gripe with television is I'm at work when my favorite show is on.'
Have any manufacturers even fixed cruise control for icy roads? That should be trivial, but no car I've ever driven has handled it.
These cars are going to be scanning constantly in nice weather, it shouldn't be a stretch to then figure out relative position with GPS and then use the distance to 'known' trees / signs / landmarks from previous trips to determine lane position.
I'm sure there are barren areas where this would be tough (I've driven I-80 through snowy Nebraska about a dozen times en route to ski vacations in Colorado) but "stay between the snow banks" should be a decent start for autonomous driving.
I now wonder if you will just pay $199 for the "blizzard package" or something. I suspect Tesla wouldn't do something like this, but just like Mosaic, they get to shape a lot of the early thought behind this.
If we assume that either all cars have the software priced in, a "good actor" would allow you to pay less for "blizzard navigation software" if you lived in S. California.
At this point, Tesla is so new that they will make it as attractive as possible and push all of their updates for free. I also have a high degree of trust, at least relative to other auto companies, in Tesla. One would imagine GM, or another less scrupulous company would try to do something like this if they were the front runners.
edit: Point taken though. I am also not keen on some of the other car and boat manufacturers producing identical engines, and then having you "pay" to unlock more horepower.