I feel awful that when I was a guest I probably left 4 star reviews for places at which I would happily stay again. You see, I actually believed Airbnb when they told me that 4*=Good. And being British, I don't go around gushing over-enthusiastically about anything and everything - I save my 5* reviews for things that are truly exceptional. Otherwise how do they get properly recognised? 3 thoughts:-
1) Is Airbnb's practice of viewing anything less than 5* as unacceptable actually tantamount to race discrimination? I suspect that people from other 'reserved' cultures such as northern European and Japanese are probably less likely to give 5* for a good but not absolutely stunningly outstanding experience, just because it's not what we do. But if hosts know we've left a 4* review, or even just see that we a from a culture that is more likely to do so, they may decline our bookings.
2) When I look through listings as a potential guest, I just have a sea of 5* listings. How do I identify the truly exceptional ones? This ratings inflation does me absolutely no favours at all.
3) The fact that Airbnb is lying to guests about what 4* actually means - any chance that a host who is delisted on the basis of their score might sue them for it? Probably wouldn't get anywhere in the UK, but maybe in the US?