A few comments obout phone-camera’s, optimistic and pessimistic.
Optimistically, I see the people who only use a phone-camera as the heirs to users of instamatics, compact film cameras with fixed slow zoom lenses, entry level SLR kits only ever used with the kit lens and in full auto mode, and those early compact digicams with sensors not much larger than in good phone cameras, and inferior to today’s phone-sensor technology. So I do not fear any loss of photographic quality there; putting aside the sometimes obsession with the artistry of heavily blurred backgrounds, these phone-cameras are well ahead of mainstream gear of the film era.
Pessimistically, I agree that the small lenses of phones, limited to about 5mm effective aperture diameter, will never match the speed and low light handling available in even entry level ILC gear, nor the quality in telephoto shots much beyond say “portrait” range. They will never match the opportunities of a 4x zoom, let alone a 10x superzoom or modestly priced two zoom lens kit.
Optimistically again, diffraction limits on resolution worry me less; these little lenses can easily handle “normal” viewing needs of say 4K across (12MP), and are already past 35mm color film. What’s more, diffraction blurring is somewhat removable by post-processing: it is a mathematically reversible process once one over-samples the optical signal enough with “excessive” pixel counts. In short, sharpening can really work!