OP, you do make a lot of valid points. Tesla does need to work on quite a few areas. Give them time, and they will. My purchasing process was... less than enjoyable.
But after owning my Model 3 Performance (well, P3D- to be more specific) for 11 days now, there is no way I will ever buy another brand. Ever.
The car is just so good that even a few horrible service experiences in the future won't be enough to turn me off to the car, and that's assuming that there *will* be horrible service experiences in the future; from what I've gathered so far (after reading everything published on the 'net about Tesla for the last three years), the average owner can expect no service visits in the first year of ownership.
On internet forums, people are more likely to complain about something than praise it. That seems to hold true on all other car forums except Tesla. Sure, there are people that post complaints, but I think you'll also find a higher ratio of people praising their cars here than on other forums. My experience, at least.
The car is so good that I'm able to overlook imperfect panel gaps and small cosmetic issues that previously would've been unacceptable to me.
The only way you'll be able to have "The Tesla Experience" is by actually going through the purchasing process, owning the car for a while, and making your own decision; give up your Mercedes and lease a Model 3 for three years. Since you get a new car every three years anyway, and you must turn your Model 3 back in at the end of the lease, what do you really have to lose? You may very well find your next car for the next 22 years.
And isn't all maintenance included in the Model 3 lease?
Ah well.. enjoy your Mercedes. Maybe see you back here in three years?