It's not "calling out". "Calling out" implies the act was done purposefully with ill intentions. It's being honest about something that will likely disturb other guests. I paid about $100/night to stay in a house in a foreign country recently. It was all hardwood floors and indoor clapboard walls so sound travelled. Luckily, everyone else who stayed there (7 bedrooms) was conscientious about noise, especially at night. If I'd had the bad luck to be next to a heavy snorer, and couldn't sleep, I would probably have asked the guest how long he was staying. If our visits were overlapping, I would have asked to change rooms and, if that wasn't possible, I would have looked for another place. (The place did supply ear plugs, but they don't really help me; I've tried them.) I might then have written a review that honestly said: "The walls are paper-thin there, so sleeping wasn't easy." Yes, guests deserve to know this.
I am a well-seasoned traveller (about 3 international trips per year) and have used Airbnb a lot. One of the worst things to happen while on vacation is staying in a place where sleeping is difficult or impossible. If a guest of mine used loud snoring as a reason to leave, I wouldn't blame them myself. I stayed in a student residence in London once and there was noise outside until 3 AM--it was partying students coming home--and when I asked another guest about it, she told me to get used to it because it happened every night. I got out my credit card and went elsewhere. (And I did write a review along the lines of, this place is not good for light sleepers.)
The attitude on this thread seems to be that the host should just get over it. What I'm saying is that maybe that's fair, but when it comes to other guests--and this host seems to have more than one rentable bedroom--I don't think it's unfair to protect one's business from bad reviews. Not everyone is a good fit for Airbnb, unfortunately.