But a watchmaker is also unlikely equally unlikely to have the skills and equipment to fabricate the individual pieces of a watch. We are asking what the repairability is like when all the pieces of the phone (that would be available in the factory at final assembly) are available to the servicer.
I think that's what they did traditionally. If you want pieces of the phone to be replaceable, you'll get a thicker, heavier phone that uses more materials to build.