I think that the OP's point is the blatant hypocrisy on the left. Not sure if you're missing the point because you're ignorant or if it's on purpose as a distraction.
The Dems attacked President Trump mercilessly during the 2020 campaign for a program that was actually begun by Obama. Now, just because it's the best choice out of a list of bad choices, is hold the children until the system can figure out what's best to do with them.
Your solution is to return the children to their parents. Let's examine the scenario:
Border patrol stops a group of four, two adults and two children. No paperwork on any of them. They can't prove or disprove that these children are the children of the adults. All four must be detained. You cannot house children with adults, because you know, predators. So, you put the adults in one facility and the children in another. That's what's going on here.