I expect that moving forward, the only business for camera repair shops are older film cameras in need of CLR. This is not a storefront service.
However, I took a stroll down my main street, and lo and behold, just south of Wellesley, there was a full service camera shop for everything: Film services, and digital photo printing using Canon Selphys. The guy told me that each Selphy was good for about 1000 prints... His business appeared to be flourishing.
The story is very different in consumer audio. People are prepared to spend serious money to have a complete parts swap. (BTW - Allen Bradley carbon resistors shouldn't be replaced with modern types (carbon composite, metal-film)). -- Except for the RIAA EQ, where many more values of capacitance are available, so 150 pF is substituted with 158 pF, 560 pF with 562... This more closely matches the intended values, simply because with more choices, a more precise RIAA circuit can be built. Surprisingly, the values of resistance in the tank circuit that is RIAA EQ., don't need to be replaced.
Most Japanese electronics made before 1980 need to be overhauled. Oddly, these inferior products seem to be coveted. If you want to examine and study excellence in design and fabrication, have a look at HH Scott. Top grade materials throughout, and a surprisingly large number of film capacitors. However, the paper foil capacitors are replaced as a matter of course.
A classic American horror story? Sherwood. Their tube gear should be trashed.