I know, lol. I think it comes down to Mini having a very limited line up, very few new parts/tech that they have to correct.
They are all based on the same basic platform and same basic drivetrains now. Interior tech is basically the same, too. That said, the F series chassis are a significant improvement over the Rover platforms from '02-'15ish. My wife has had an F54 Clubman with the B46 for almost 8 years now. We had a stuck parking brake (warranty), some tabs on the cupholder came loose (warranty), an evap valve ($150, 15 minute repair), a new 12V battery ($250, 15 minute repair), and front brake pads ($100, 45 minute job). As much as I'm excited to have it off the books when her UX comes in, I can't significantly complain about the quality of the vehicle. I do believe that they are a car that needs to be pampered a bit. Hitting potholes on the regular is going to wear out suspension components and those hits will cascade into interior clips. I don't get the feeling that it is built quite as robustly as my Toyotas.