The stuff that Rossmann repairs are "simple" because he has the tools and expertise to do so. It's very much a "$1 for the screw and $999 to know where to put it" type of situation.

Does everyone realistically expect Apple to have a Rossmann-level repair person[0] in every one of their 528 Apple Stores to do these "simple fixes" with professional gear.

Or is it actually more economical for them to build the equipment for swapping whole boards so simply that anyone with 30 minutes of training can do it. (This is the gear they rent to you when you want to self-repair btw)

[0] 3+ more likely so that they can have vacations and sick days too