I’m not a scientist but I think it’s a few things. Young and old people poorly educated on information. They believe anything on social media not knowing the source. Because it looks cool or fits their lifestyle. They are very easily influenced by friends or things they think they trust.

Thinking that someone else has the answer that fits their narrative instead of no or a negative answer. There are many groups that think that they don’t have mental illness yet science hasn’t “figured them out yet”.

Trusted information sources that slowly went in a different polarizing direction like Fox News or local tv stations owned by Sinclair media (plus many more companies).

Also social media is full of bots and fake information, but it’s subtle so it gets away with it. I’ve seen blatant fake information on twitter disguised as news, nutrition, exercise, people. If it’s subtle enough no one is going to notice. Also with our phones, streams and other things coming at us we ingest so much content at one time. People don’t stop and look at it for what it is, they just move to other things and bite size information it what gets through.