He should have long deported, but he wasn't. That's on Obama and Trump. There is no getting away from that. He was 'kept' here.
The fact is there were higher priorities. You have a single example of a DACA killer. But there are 1000's of non-DACA criminals that have been deported. More importantly many illegals have self-deported which is our only solution for the millions of illegals.
The other fact is Trump changed his mind. He likes DACA people now. The sooner you accept that fact and move on, the better.