It seems like a very specific thing for a reporter to ask and find out about.
If you know what you're looking for in those, you can identify a lot of different phosphor configurations just by the particular shape of the RGB peaks - the older ones have a distinctive multi-peaked red emission that I've seen in various LED bulbs as well over the years.
I doubt Apple mentioned it to anyone. Applying a spectrometer to any new light emitting device is just the sort of thing some people enjoy doing.
They're officially just called "Posts" now. It's a hell of a downgrade from how distinctive the old terms were, no wonder people still call them Tweets.
Community Notes was also set to be called Birdwatch originally, continuing the bird pun theme.
https://pages.ucsd.edu/~dkjordan/resources/PronouncingNahuat...