I've come to find out that older folks — somewhere around 50+ — have been the worst possible guests, with no exceptions so far. They tend to be stingy with their star ratings and leave poor reviews even if they had a perfect experience. They also tend to be much more high-maintenance and not self-sufficient, acting as if they think the Airbnb is a hotel and the host is their concierge or room service.
The cost-benefit ratio doesn't work for me in these cases, so I've been intentionally passing on older people recently and trying to fill my Airbnb with younger folks. I never see age mentioned as a factor for discrimination in articles like these, and it seems that it may not be legislated in the same way that the other factors are.
But it feels like it's the exact same issue, and I'm willingly becoming more and more guilty of it.