There are definitely two sides to the story, and a certain amount of research will make that clear, which the OP does not acknowledge.
The controversy was a very specific and cruel Trump administration policy to separate children from their families by automatically criminalizing crossings (typically border crossings are civil rather than criminal offenses, until criminality has been established). It specifically came out of Stephen Miller's 'zero tolerance' policy for illegal immigration. Many of those involved (with the strong exception of Miller himself) have expressed regret for enacting the policy, because it led to permanent separations of children from their parents, before the typical standards of criminal behavior were met. Obviously that is a tremendous trauma for children.
Indeed, there has been misinformation from the opposition, taking pictures of children behind fences out of context in order to make the policy seem more cruel. While in my strong opinion the policy was cruel and was very much intended to be cruel, people on all political sides can and do use social media manipulations to make fallacious points. It's never just 'those people' doing it. So the waters are muddied. I think a good HN post acknowledges the muddiness of the situation, rather than a black-and-white pronouncement--hence the downvoting.
Probably for implying that Trump wasn't that bad, when he clearly was.