My impressions of Tesla build quality don't align with yours, I find that interesting. I won't argue that Tesla moved the needle extremely far; I have been on record for saying that the Model S was the first car to come along since the Citroen DS as an individual model shifting the automotive paradigm, and the fact that Tesla successfully launched a mass market car company without first having their products labeled as utter garbage makes them a first for as far back as I can recall. And I think the launch of the Model 3 as a car as successful as it is, of a quality that perpetuates that success, is also truly remarkable.
But I also think there are a lot of 'problems with EVs' that are more 'problems with Teslas' that have been used as a reason to avoid the adoption of EVs.
That being said, if you follow the trail of Mercedes-Benz back far enough, you find Gottlieb Wilhelm Daimler and Carl Freidrich Benz, and I don't think anything can eclipse the paradigm shift they brought to the world in terms of personal transportation, besides, possibly, the invention of the wheel itself. Do you?
Here's another point though. Some of Mercedes innovations have either been a bad idea, or a developmental dead end because of excess cost and complexity. An example of that is mono-blade wiper that debuted on the W201 and stuck around through the end of W210 production. It is a superior design to any other wiper system; it is also so expensive and complicated that it ever being adopted by anyone besides Mercedes was unlikely, and ultimately, even they couldn't justify the expense.
I can come up with three such features right off the top of my head for Tesla. The first is the X's 'falcon wing doors'. I don't think I need to explain why they are an example of what I'm talking about, do I? They are so pointless and over-engineered, I suspect Musk stole it from a DB engineers in the first place. The second is the stainless steel skin of the Cybertruck; building vehicles out of stainless steel has been a thing since Edward G. Budd invented shotwelding in the 30s, and it has not caught on in private cars for a reason: it makes sense for insanely durable commercial vehicles like railcars and line-haul busses, but on a car, its an expensive gimmick.
And the third is megacasting. Tesla didn't invent that; Mazda did. The Millenia used 'megacasting'. It has a series of benefits in body fit, apparent quality, refinement, and body stiffness. It also is a really bad idea in a production automobile. Car bodies being assembled out of a series of different components makes accident repair and general maintenance much more expensive; its a major reason why insuring Teslas is so expensive; they total really easily because repair of the megacast body is prohibitively expensive.
Cars have to make sense in an environment where they get disposed of fairly rapidly, and get beaten up in daily use.
I've driven Subarus hard. If somebody put a gun to my head and told me I had to buy a Japanese car, after I tried to argue cruel and unusual punishment, I'd buy a Subaru. Probably a BRZ though. Rear drive is non-negotiable for me.
I certainly can appreciate your like of the 850; for a wrong-wheel-drive car it is remarkable, and one of my favourite cars of the 90s. Although to my recollection, AWD debuted on the S70, rather than the 850. (Apparently my recollection is wrong; the S70 is just an extensive facelift of the 850 anyway). If I had to buy any car of the 90s, now that I can import what I want, I'd import an E300 diesel wagon, and swap in the turbo. I can't think of a more perfect car that would serve every possible need perfectly.
Bias can create strange feelings sometimes; ever since I can recall seeing the first W124 I ever saw, I thought it was the most beautiful car, and ever since I first rode in one, I was in love. Buying one didn't assuage that. Nothing quite combines modern car design with old-school MB build quality quite so well. You have to admit, nothing feels quite as solid as a W124.
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