This is not so much, in my mind, about the upgradability, it is about replacing your SSD when it fails. And if you look at the specs of Apple’s SSDs, the TBW, the larger ones have a larger TBW. I would also urge everyone reading this to contact their State representatives about “Right to Repair.” This would allow repair shops to be able to upgrade or replace your SSD on your Mac Mini or MacBook without voiding your warranty.
Now, do this on a Mac Studio!