Wonder how much of the crash is from coffee vs the sugar (the post mentions hazelnut lattes which should be called hazelnut-flavored coffee/sugar drinks).
I went very strictly non-sugar for a month or two a year or two back. I noticed that I had no desire for caffiene in the morning (not that I am a huge drinker, but maybe a couple of mugs of green tea to get me going).
Sugar definitely induces crashes, but caffeine by itself does as well. My flirtations with coffee/sugar monstrosities were temporary; I mostly drank espresso-based drinks without sugar or sweeteners.
A sugar crash happens two to 2.5 hours after the last sugar consumed.
So, it's not a sugar crash the author is talking about.
Perhaps, but at 10 beverages a day caffeine is only part of the problem since they were no longer drinking black coffee. Even plain cow's milk on its own has some sugar.