Anecdotally I've known 5 BMW owners, one was an older car (early 2000's), the rest made after 2010. The older one wrecked unfortunately, and all but one of the rest had mechanical failures.
Statistically they may not be any better or worse than any other manufacturer, but I still can't convince myself that their craftsmanship is any better. The koreans pride themselves in their craftsmanship too, and their cars are a third of the price.
Anecdotal too but the only car that has left me stranded ever was a bmw.
I love the older bmws for the driving experience but they require so much more maintenance than say a Lexus. The newer bmws meanwhile seem to be geared much more to the luxury market than driving enthusiasts (eg very few manual choices).
Ironically the least solid, least reliable car I have ever owned was a Toyota. After 8 years it was very poor. Other, older, cars I have enjoyed more reliability with have included a Honda, a Kia, a Fiat and a Lada.
(more anecdote) I've known a few people with corollas and drove them for a long time. All of them have been in pretty bad shape after a while. Engines running rough, lots of physical damage, struts and springs busted, little bits and pieces missing / not working etc. In fact all of them were pretty scary to drive and ride in.
In general they were all beaters that barely ran, but they ran. One corolla went for 2 or 3 years without an oil change and had 2 cylinders with low compression. Friend never got it fixed, but the car was still running (although with very low power). I actually think the general reliability of these cars leads to them being in worse shape. They're running so why bother to fix it. The owners also had a drive it until it dies approach, just generally took a long time to die.
Statistically they may not be any better or worse than any other manufacturer, but I still can't convince myself that their craftsmanship is any better. The koreans pride themselves in their craftsmanship too, and their cars are a third of the price.