Pretty common. Experimentally, it seems the implicit formula many use for IM is something like
Fewer than K words + a period = probability P(deliberately curt) = 50%, where K is at least 5, and P increases logarithmically as K approaches 1.
Which is how, to someone using this formula internally, “Great.” can denote exasperation, “Thanks.” can imply strained manners, and so forth 🤷
I remember when I started encountering somewhat younger adults verbally spell out chat acronyms like “lmao” and “rofl.” I thought it was hilarious, but eventually realized there had been a social shift. Interactions had become online-first, and for some younger people that was basically all of it, and I wasn’t sure how I felt about that.