Depends. I'm not sure you could make a business out of just fixing monitors. As another thing the phone repair shops can fix - maybe?
As for why? $ per benefit.
I had a pair of Samsung 204B screens I liked. I didn't see dollar per benefit in upgrading from 1600x1200 4:3 to 1920x1080 16:9.
They went funny, I obtained a capacitor, pop the back off, unsolder and solder new cap, put the shell back on. Job done. 20 minutes per screen because man, am I bad at soldering...
They worked happily for another 5 years each. Until society got well past the 1080p rut and into proper 1440 and 4k etc screens which were actually worth upgrading to.
1920x1200 in 23" or 24" were an OK upgrade from 1600x1200 CRT 21" for me. I did the stuff you did on an 18" 1280x1024 SPVA LCD from Fujitsu-Siemens. Since I hadn't soldered for a long time, I just bought that stuff 2 times, because the parts were a few cents only. Didn't need them 2 times, though :-) Worked for some mainboards in similar ways. Except I've been afraid to completely desolder them on mulitlayer mainboards, for fear of destroying the VIAs/through-holes. Just pulled the capacitor from it's pins still stuck in, cleaned them, and soldered the new one(s) onto the old pins. Looked like sort of a water tower in miniature, but the boards worked flawlessly afterwards. For years :-)
As for why? $ per benefit.
I had a pair of Samsung 204B screens I liked. I didn't see dollar per benefit in upgrading from 1600x1200 4:3 to 1920x1080 16:9.
They went funny, I obtained a capacitor, pop the back off, unsolder and solder new cap, put the shell back on. Job done. 20 minutes per screen because man, am I bad at soldering...
They worked happily for another 5 years each. Until society got well past the 1080p rut and into proper 1440 and 4k etc screens which were actually worth upgrading to.
Edit: make shorter