I think you must move on from your memories from your childhood . Technology has changed so much.
I'm not sure if you can get portable units that are actually air-con and not evaporative units, but air-con is so cheap these days to install that I reckon you'd probably pay nearly as much for a portable one as a split.
But A/C still breaks down nowadays. Just like everything else, despite the advances in technology.
I will get A/C if and when I really need to. And just bear the cost of repairs, like I bear the cost of repairing everything else (plumbing, car etc).
I personally almost never sleep with A/C on. I don't like artificial temperature control. I dislike hotels which have un-openable windows. And I don't understand why hospitals aren't open air. Isn't A/C just circulating all the germs?