@MichaelDP....&...."how many people could actually fix most electronics".....I would guess the literal answer to that question is likely "none"; that is, I doubt seriously there is anyone who could fix most electronics simply because any one person, even with remarkable technical skills, would never live long enough to "fix most electronics".....but obviously your question is likely, "How many people are capable of repairing a broad range of electronic devices?", and the answer to this question is "a large number".....which then begs the question, "why are there so few electronic repair shops//repairmen?" And the answer to this question is actually quite complicated in some respects....and quite simple in other respects....The simple answer is: "Repairing electronics is not generally an economically viable pursuit."
You might argue that you, "made $100 for less than an hour's work! Obviously that SEEMS like GREAT money!" And obviously if you could repeat that task 12 times a day you would be well on your way to making a good living....but there-in lies the rub....even if the vast majority of electronic repairs were "simple" there are at least two other components to the rubric: 1) Acquisition of "broken" electronics 2) Selling the repaired products after they are repaired. So if you look carefully at the skill sets requisite they now include, 1) Electronic Repair Skills, 2) Acquisition of Appropriate Materials 3) Sales...but assuming this is a business you would also need to add 4) Accounting Knowledge and 5) General Business Knowledge/Skills....While the last two skill sets may seem trivial, they are the second leading cause of small business failures in the US....the first being the various governmental agencies associated with levying and collecting taxes and enforcing various "consumer, employee and environmental oriented regulations/laws"...which are arguably a result of lacking requisite skills #4 & #5....Most people find it difficult enough to master just one of the a fore mentioned skills and generally spend their working careers earning a living with that skill....
But you didn't directly ask, "Why aren't there more small businesses repairing electronics...", you asked, "how many people could actually fix...." to which I responded, "a large number"....but a large number in no way implies a "large percentage". Assuming even one in a thousand people has the skills to repair electronics this would imply one million people per billion....or, as of 2014, roughly 7 million people....obviously the accuracy of this number is predicated on the accuracy of 1/1000 which is just a SWAG used to illustrate that the fact that you might not have ever met anyone who has the skills to repair electronics does not imply the number of people with the skills is "small". I would also estimate that perhaps half the people included in the group have little or no formal education in electronics, but are "self-taught".... Hobbyist if you will....
And, finally, "Who are these people with the skills?" And, "Why don't I hear more about them?" While I stated likely half the people included in the group have little or no formal training in electronics, the other half are almost certainly highly educated/trained specifically in electronics with the vast majority of them having engineering and/or military backgrounds. I would also estimate that a large percentage of the people in the group w/o formal training acquired the skills from parallel interests in radios/computers/RC/Automotive etc hobbies/careers...or in some cases simply because they like to "tinker" with things and over time have added electronic devices to the list of things they "tinker" with. As someone who has a long history of dabbling in electronics, I will say attempting to talk to people who don't have any background in electronics about electronics is much like trying to explain the nuances of a poem to someone who doesn't speak the language the poem is written in...it wastes your time and irritates them. Even worse, if people who know you, KNOW that you "work on electronics", they assume you can fix anything from a toaster to a motherboard and that it would be "simple for you to take a look at it for them." Speaking for myself, I make every attempt to disavow any rumors that I know anything about electronics to "casual acquaintances" and at times even good friends simply because I don't want to waste my time on their problems....but despite my best efforts I occasionally still get suckered in....lol....and the old adage, "No good deed goes unpunished"....slaps me in the face
Hopefully something in this diatribe addresses your question....
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