The article was crap -- it's just that humbled, like words often do, has shifted meaning in the last few decades to mean something between "proud to" and "I didn't believe that I'm that worthy, but if you say so", etc.
It happens all the time with all kinds of words, e.g.:
"The oldest meaning of awesome is “something which inspires awe”, but the word is also a common slang expression in English, originally from the United States. As the original meaning of awesome has become somewhat antiquated in general use, the term awe-inspiring is now generally used for the same meaning."
The parent's point is that it wouldn't feel humbling in any original meaning of the word. You wouldn't feel "lowered in stature" etc for being chosen, but the opposite.
But of course this ignores that the word has shifted in use.
The hot 10mm rounds are usually reserved for subs like the MP5/10 or special units. Grunts would get regular loads similar in every manner to a 40cal.