That you see them on "business types" tells me all I need to know about their prospects. BlackBerry used to be the go-to phone of "business types," too, and look where they are now.
Debatable. I have yet to hear a compelling use-case for a foldable phone that justifies their high cost, weird dimensions, terrible durability, and that massive crease in the middle of the screen.
Does it? I haven't seen numbers on this, but I'll bet that Apple sells more iPhones in a week than all companies sold foldables last year. Which isn't to say that foldables will never be commercially successful, just that they aren't now and probably won't be unless/until Apple releases a better one.
Like what? The only thing I can think of is an OLED screen. 5G was definitely not "standard" at the time, and Apple probably jumped the gun a bit on introducing it on the 12 Pro at all. ProMotion was introduced on the 13 Pro, but high refresh rate was also not standard on phones at the time and had been a selling point of the iPad Pro for years.
I fail to see how the success of the iPhone can in any way be attributed to things that had been standard on Android. Titanium? Not remotely close to a "standard," even on Android flagships. A 5x telephoto? Arguably common on the absolute highest end of Android phones but far from a standard. USB-C? Absurd.