Every issue you’ve mentioned absolutely exists… There must be an enterprising CEO or two out there…
Craig Morrison

Such CEOs exist, but a) they’re not CEOs of US-flagged airlines and b) US and US-dependent-country airlines (I’m looking at you, BA, in my experience) have regulations that prevent such customer-oriented reforms from occurring. Starting with the imposition of security theatre as a replacement for genuine sucurity. Want to see how professionals do it? Go fly El Al. The country is beneath contempt (IMO), but I have the highest respect for the professionalism and competence of their airline-security people. They focus on people, not on ticking bureaucratic boxes. How much more foreign to the US flying experience can you get?

I will use any means necessary and available to get flights changed if I discover I’ve been booked on a flight that’s code-shared with a US carrier. It’s just not worth the stress. I’ve flown on 40-year-old Soviet-built airliners. I’ve flown on some incredibly shitty third-world airliners that seemed highly unlikely to outfly an unladen swallow. Those have been heavenly in comparison to the last dozen flights I’ve taken on US airline-originated or -code-shared flights. Life is just too short.