Initialisms in common speech are the linguistic equivalent of a code smell; people are right to react negatively towards them (and the appropriate degree of negative reaction increases with the length of the initialism in question).
I was talking about spoken language, not the existence of initialisms per se. Though I'd wager they are a lot more prevalent in written American English than in most other languages as well. Nobody else would think of inventing an initialism-euphemism for body odour (which I guess already is a euphemism for "smell" for example. Or "significant other".
By the way, QED is just a calque from Greek. (Like most things Roman...)
Funny, when I was born and grew up outside the US it was very common there too. Perhaps you'd like to scope your claim down to a specific group of people who find it annoying?
Again, that might work fine for veterans, but not for victims of peacetime rape and horrific accidents who have similar symptoms. The syndrome needs a common name, like: he has “the horrors”.