The one argument in favor of camera swap, specifically, is how much of a (good) camera is in the optics and the sensor size (not necessarily resolution; but more physical pixel-sponging goodness). Both of those things are expensive, of interest only to a subset of users, and occupy additional space; but electronically, crunching the output of an X-megapixel sliver of bottom of the barrel silicon behind a shitty plastic lens is identical to crunching the output of an X-megapixel DSLR-quality silicon sensor mounted behind the finest in multi-element fancy optics.
This concept piece carries modularity to an arguably pointless extreme, given that modularity has costs; but for specific components(like the camera) where logically-equivalent parts can differ wildly in performance depending on how much you care, modularity might actually work:
Consider the following rough-cut proposal: mechanical mount (parallel rail or circular twist, to suit) with MIPI CSI-3 interface broken out into contacts, along with power and ground).
It wouldn’t make sense for the real cheap seats, the physical connectors alone could cost more than the ‘.3 megapixel’ wonders in your basic feature phone; but for more photography-oriented cameras(like the Lumias) it’d allow you to trade off anywhere between ‘minimal bump, easily pocketable’ to ‘performance equal to the finest sub-DSLR’ (since there’s no actual room for a mirror assembly) as occasion suits.
