4-elements Monk

[KorvinStarmast]

You can't just give the Four Elements Monk spells and abilities that would fit its theme! Don't you know that making the Four Elements Monk interesting, useful, or fun runs counter to WotC's design goals for the subclass?

What design goals? Evidence?

There isn't a blurb that separates mechanics from fluff.

You are correct.
There was such a blurb in 4e, but in 5e you see an assertion that "x is fluff" then you are dealing with someone who is perhaps making stuff up, is offering an opinion based on some other edition, or may be trying to be dismissive of "point x"