That’s just pointing out upgrades carry a large price, not that the base model is at a loss.

Which is a super common strategy in pre built, especially in systems that can’t in theory take third party upgrades. Commonly a mobile platform will charge a hundred dollar premium for like 20 dollars worth of UFS storage. At least at some points PC vendors have done DIMM SPD lockouts to force customers to first party so they can charge a significant multiple of market rate for their parts.

I doubt anything in Apple’s lineup is sold at a loss. They might tolerate slimmer margins on entry, but I just don’t think they go negative.