That is because many companies offer as many options as possible to maximize their sales, while Apple curates their offerings (less well than in previous years) to remove all the troublesome work of sorting through a matrix of options. In Apple-land, the idea is 'we did all the hard work of deciding what you need' (and I guess you could argue part of the price is paying for that curatorial work).Apparently Apple users DO care about specs like OLED since Apple went through all the trouble of putting one in the latest iPad Pro and they're selling like hotcakes (9M did I read?)
If you don't need or want or can't have an OLED then Apple has an iPad Air for you. MacBook should have options for OLED and options without. I can configure a Dell or an HP or a Lenovo with or without an OLED depending on whether I prioritize battery life or display quality. Can you even imaging Apple giving the customer a choice like that? I can't.
Not that I am for or against either approach, it just seems that curation is very much of what makes Apple what it is.