So let's do some unpacking here.
First off, let's quit pretending that these issues are new. Right off of the bat the last Presidential administration went to court to defend the idea that illegals could be held indefinitely and without contact of lawyers and loved ones in detention centers without any legal rights. People were held for years without hearings, or even the government acknowledging that these people were being held. Even if you don't want to buy into what the right wing machine is putting out there in these regards you can look up PBS Frontline episodes on immigration over the years, and you will see that this goes back a long way.
That said, if Trump really wanted these policies changed, he would have. The man picked right up with the last President's frequent usage of the Executive Order as a means of fiat legislation making. He has not hesitated for a second to use EO's to do whatever he feels like. He has also not hesitated in making a public mockery of the law, the legal community, and its enforcements whenever it was against a belief he held, so I don't believe for a second the crap about it being a law and order thing. If he really felt the policies were unjust and needed to be changed, at the very least we'd be getting a twitter fit about them.