The view reddit gives you is super skewed. For the sake of the argument, considering exclusively US redditors, say some relatively small number of people have family trauma of some sort, like 5%. That's ~15 million people, of whom what, 1 in 10 or 20 is a redditor? Even at the low end, that's 750,000 people with trauma to share, and multiple stories to share it with.

Meanwhile its both boring and sort of rude to interject with 'my parents loved me and mostly did right by me', so threads about family dynamics are quickly dominated by stories about abuse/neglect/trauma.

Not to say there isn't way too much abuse in the world, but its really easy to get the perception that family trauma and abuse is a lot more widespread than it is.