There’s a pretty simple correlation most of the time: the cheaper the accommodation compared to the local market, the higher the chance of disappointment.
On the other hand, when I take Airbnbs that are only a small discount compared to a reasonable but completely average hotel room from a reputable chain, they are often fantastic.
Bad and scammy holiday and short term accommodation is surely a problem, but Airbnb and their rating system doesn’t look any worse than many other alternatives from my experience.
Many of the comments here show more about the author’s attitude toward a once popular start-up than much else.