Home HVAC is the most obvious current regulatory caused scam in the US. Virginia just added an 'easier' license that 'only' requires two years of experience to receive (and 160 hours of formal training, but that's not the bad part obviously).
Something like a minisplit though can literally be DIYed in under a day. With experience, a DIYer can do it in a couple hours. They're literally designed to be easily installed as a complete system. Even in Japan you can get one installed for under a grand (including the unit). In China it's obviously even cheaper.
Obviously HVAC companies don't want it to be easier to get a license, they make boatloads on entire home systems and maintenace. Being able to just replace a broken unit for $600 would kill their entire business model.
Electrical is a similar scam, though for some reason if you get enough quotes you can usually find one that isn't charging the equivalent of $1k/hr in labor like getting a mini-split from an HVAC company tends to be.
There indeed are plenty of mini-splits you can just buy & install.
I would too. Alas mom lives in a northerly area, and we really would prefer something high efficiency. There's some rebadged 37mpra units about that are 35+ SEER2, which if the number means anything is a colossal leap. The good stuff though doesn't seem to be directly purchaseable. I'd be happy to lay the concrete bed, set it up, drill walls, mount the ductless... Getting help actually vacuuming would be good but I could do it.
But I can't go purchase the system.
It's all deeply infuriating. This is just such a rude awful thing that American society keeps having to put up with such deeply captured deeply absurd base costs everywhere. These tradespeople deserve to make a living, I don't bergrudge them that, but this feels like there has to be so so much more going wrong for these prices to escalate like this.