I bet if it was $100k salaries for ALL technicians there would be no shortage.
Of course this would cut into profits.
Of course this would cut into profits.
And for all the owner-operated mechanic garages out there, which is probably the majority of them, their profit IS the labor bill. "cutting into profits" while raising salary are literally opposite concepts.
OTOH, at some point outsourcing will become a viable alternate.
Pack up all the cars that need expensive repair, ship them to Mexico for fixing, ship them back once repaired.
Or you call a plumber for a simple repair and there goes one kilodollar, while the guy doing the work gets a few hundred of it. The rest is all going to the overhead of phone answerer, scheduler, manager, business entity owner, franchiser, etc. I suspect the majority of "cost disease" is going to such intermediaries, and the thing about intermediaries is they know their main job is maintaining their position.
The trades are relatively efficient at forming new entrants. Most of the plumbers, painters, carpenters, et cetera I've worked with ran their own businesses. That didn't make them cheaper.
I think this somewhat ties into business discovery getting harder. There was a period where the Internet was making this better, but has now been seemingly completely locked down by web spammers and the surveillance-adtech industry making it into a pay to play game (aka more overhead). I'm halfheartedly in the market for contractors myself, and it seems like the best way to find leads is to sit down for lunch at a restaurant next to a main road, and write down the phone numbers on the trucks going by. At least that only requires people to spring for the fancy truck wrap, rather than the fancy website and surveillance-based advertising.
[0] My aunt's drain was slow and I was too swamped to look at it, so that's who her helper ended up calling (sigh). If I had known the bill was going to come to $1200 for installing 12 feet of PVC pipe, I would have made the time.
[1] Warranty recall.
The good news is, in most towns, you only need to do this once. From there you can rely on referrals.
If you start a shop, you will quickly find that many customers want mints on their pillows and telephone sanitizers - Even if as an owner, you would prefer to fire the lot of them and take an buy a new vacation home.