For the most part, these are the same people that were working there doing the exact same job in 2014. They don't view themselves as doing anything wrong because they have seen enough of the bad shit that cause Obama to implement this policy during his term.
The only difference is the volume of cases come in. The administration gave an order to reunite the families with the kids but there is quite clearly a bottleneck is in this process. We don't have the infrastructure to house all these people and definitely don't have enough case workers able to get them through the system. Sessions started this DNA solution but that's not exactly a quick solution.
I don't think anyone wants kids separated from their actual parents and that's not what this policy was designed to do. What it's supposed to do is to stop kids being tortured by actual bad guys.
Obama's policy was catch and release because we don't have the infrastructure in place to stop the bad guys. So his policy was to just let them through and let the local PD handle it. Trump wants to stop them from entering in the first place but is having to settle for this hybrid system that basically forces the US to house these people until they get to see a judge.
So the real debate is how we stop kids that are crossing the border illegally from being tortured without them ending up in cages in the process. It's a problem and I don't think you can solve both by just blaming the other side.