Tough to trust this analysis... For example Cadillac is the #3 worst brand yet there are no Cadillac models in the worst 20 models.
BMW parts are expensive.
Your answer doesn't help understanding how the article finds the average BMW maintenance cost to be higher than that of the BMW model with the highest maintenance cost. Unless brand costs are not calculated as a mean but something else very different, which is not explained.
Apparently, the 328i has a relatively common oil-leakage problem. http://repairpal.com/bmw/328i
Don't have the labor costs for a valve cover gasket, but they could be sizable. Scrolling down on repairpal web page above, apparently they can cost up to $1000?
No wonder BMW 328i is in the higher range for maint. costs!
The problem is that paying for parts and parts replacement piece by piece is significantly more expensive than buying a new bike (or a car) as a whole.
Repair costs like that adds up quickly. Like the $1200 3rd row seat motor that died. She started calling it the thousand-dollar-car, since any repairs were around that price.
None of what you describe is unique to Cadillac -- this is what it is to own a luxury automobile. If it is not worth the price, don't buy one.
Which may be one reason why Lexus unexpectedly has a good total cost of ownership.
BTW, the Lexii had far fewer squeaks and rattles after 6 years than the Cadillac did, and had a much quieter ride overall.
As another commenter pointed out, this is quite common on performance and luxury vehicles because it has handling advantages. If you're buying a luxury car, you're by definition choosing to pay more than is absolutely necessary for (what you consider to be) a better experience. The tires are part of that. You can argue that the line should be drawn elsewhere, but it's not arbitrary, and it's very much in line with the market segment they're going after.
It's a SUV. They get used to tow boats, take science-fair projects to school, and take the family on vacations. They aren't used for track days at Road Atlanta.
Performance vehicles I disagree. Handling choices are up to the mechanic/driver and you want to give them options but also make their maintenance choices simple. You should have a wide range of tire options on a performance car.