The "past few years" is a bigger sample than just "the past year", so assuming the posts are equally distributed through time, you're still going to get more of them in the first bucket.

Still, from the top 10 of past year:

"Why Airbnb is dead to me" (https://news.ycombinator.com/item?id=10291070)

"The two faces of Airbnb" (https://news.ycombinator.com/item?id=10487447)

"AirBNB why did you terminate my account? – An Open Letter to AirBNB" (https://news.ycombinator.com/item?id=10090119)

"Living and Dying on Airbnb" (https://news.ycombinator.com/item?id=10531229)

And many of the others in the top are not really about AirBNB itself, just of related topics. I don't see much praise.