Excellent point.
I think about wording like that, like the extraneously explicit meta-content that dumbs down so many story plots. A character explicitly says "That makes me angry". When a better written story would make the anger implicitly obvious.
Stories should show not tell.
Make a point, make it clear make it concise, and it will be simple for most readers. Don't talk about making a point, or say a point is clear.
That is projecting attributes or experiences onto readers. But even a very well written point may not appear simple for some readers. Assume (optimistically!) that there will always be some unusually under-prepared but motivated reader. Hooray if you get them! They can handle a challenge every so often.
"Simple" communication is a high priority target, but rarely completely achievable for the total self-selected, beyond intended, audience.
The good ol' "this proof is trivial so we'll skip it" move.
Oh man. The variant I see so infuriatingly often at the moment is “It is clear that these form a Lie algebra/finite abelian group/Hilbert space/bijective map/<whatever other thing that is long-winded or complex to prove> and I encourage the reader to satisfy themselves that this is the case”.
He should have really used the good ol' QED instead, lol