Does North Mexican Spanish sound "angry" to native speakers of Spanish from elsewhere?
It's true that I have not spent a huge amount of time in northern Mexico, but I still would venture an answer to this of "No," and here's why: I learned my Spanish in Mexico, and wherever I go in the world, people (Spanish speakers, that is) quickly identify my Spanish as Mexican, and no one reacts to what I'm saying as though they felt I sounded angry. (Unless I really am angry.)
The attitude of the speaker made me uncomfortable, in a number of ways, for example:
her criticism of the northern vocabulary such as "ride," "troca," and "inmueble"
her criticism of the northern intonation patterns
her identification with her fellow foreign missionaries
In fact, what I could glean of her approach to being a missionary didn't create a positive impression.
In short, her editorial, if that's what her youtube recording was, struck me as thoroughly subjective and culturally arrogant.