I totally disagree that 30 something women are single for a reason shibboleth. I’m a single woman in my 30’s and I have absolulety no ridiculous character traits or baggage, am very good in all social situations and love the outdoors/camping/music festivals/a good night out with mates. I’m not a minger either!
I’ve had a few dates from POF and everyones been much more normal than your experiences. I believe thats to do with how I filter them based on responses on emails.
Maybe your personality attracts these kind of people? Or maybe you just need to filter more carefully.