This thread got off its intended course I think. The OP was focused on usage of a new phrase, not errors. It's not even that subtle of a difference, so I don't know why a familiar trope got resurrected here rather than the intended discussion. Then again, I'm an old man and everyone is usually on my lawn.
I find the use of "low key" interesting and not very annoying. Yet. It has the potential to get there. But as of now, it's an interesting descriptor.
The one that gets in my craw these days is "in a minute" or "for a minute" when used in the dumb fashion that's still sort of popular (but fading, thank goodness). Like when you haven't played ping pong in 10 years and your friend challenges you to a game and you say, "I haven't played ping pong for a minute." Or, "Damn, Steve, how you been? I haven't seen you for a minute."
That's just trying too hard. It's not interesting. A minute means a minute, and already has a slang use of meaning a short period of time, like as in "i'll be there in two minutes." Don't muddy up the waters and infringe on "a minute"'s current role in the universe. You have other options.