Agree on mechanical and medical, but:
> Hobbyist wall wart vs. professional wall wart – which one should you be able to trust more not to burn your house down?
I will trust a well-known brand with lots at stake, like Apple. But on the other end of the spectrum, I would put more trust in a charger built from ground-up by a hobbyist I from my local Hackerspace than I would in a random charger off Amazon or AliExpress (and in fact, I had two no-name multi-port USB chargers from China fry themselves).
In general, I'll trust a hobbyist that cares about their craft more than someone doing it for money, unless the latter has their own skin in the game (e.g. doing a bad job would cost them real money, I can sue them, the government could put them in jail).
So with civil engineering, medical care and car manufacturing, I will trust the professionals - because there are strong legal incentives stopping them from cutting all possible corners or doing lots of nefarious things (that doesn't stop these industries from trying, though). But software is a completely different story. There's no protection, no incentives to counterbalance the sociopathy that arises when one optimizes profits too strongly. If you look at modern software, it all looks so great at the point of sale. The bad things - vendor lock-in, excessive telemetry, bad security, selling people out to advertisers, leaking the data due to bad security - all those things hurt users post-sale, and companies know that none of this meaningfully affects their profits in any way.
And even looking at the "normal" industries - at their culture - I have the impression that it's not the "for money" part that's responsible for quality, but the counterbalancing incentives; I think all these industries would be just as bad as software if it weren't for the regulation that retards the profit optimization.