Micro LED has been rumored For the Apple for years. They actually purchased a company back in 2014, known as ‘Luxeview’, who actually developed micro LED panels, in which Apple ‘bought out’ that company likely for R&D purposes. I assume the first time we will see Micro-Led will be the ‘paradigm shift‘ for the Apple Watch, then transition over to the iPhone. Mini LED will be another spectrum probably for the iPad and MacBook.
The reason Micro-Led will be a major key point for Apple in the future, is it has significantly less power draw over OLED, which will transition to extended battery life. Plus, it allows for a higher brightness, wided-color-gamut and increased resolution.