Less than 1% of MBP and MB buyers ever upgrade their SSD.
Sorry guys but Apple builds products for the majority, not the minority.
Apple builds for expedited obsolence. It doesn't have any customers in mind. But you are correct the majority of non-pro consumers wouldn't dare crack open their MBP. But the point here is, what is the practical reason for using soldered storage in a premium notebook? Even if most users don't upgrade their storage why shouldn't that option exist if it doesn't affect design which doesn't look like it would here. Certainly upgradable SSDs would improve resale value which IS a selling point.