I've discovered two YouTube channels called Macken Murphy and Wheat Waffles who both use studies to give men dating advice (e.g. studies about women's preferred level of mascularity on men). Wheat Waffles in particular has no scientific integrity at all, and only cites parts of studies (like graphs) that he always interprets in a very pessimistic way. I see this type of thing all over the self-help community. Macken Murphy has an academic background, and (to a layman like me) appears to take a lot more care to maintain scientific integrity, but I can't help but wonder if isn't a bad approach.

My logic is that these studies become more accurate as the sample size increases because it averages out and individual idiosyncrasies are less likely skew the data, and therefore researchers take care to get a large sample size. But if this is the approach that researchers take, wouldn't that mean that on an individual level there might be too many other things that need to be taken into consideration for research to realistically reflect an individual's situation?

If anyone has a good resource about psychological research and how it can and can't be applied I would be interested in it as well.