I believe I’ve heard him say it doesn’t make any sense for us to educate these people and then force them to go home meanwhile allowing less educated people in.
Trump doesn't need to be promoting this because there is a real question whether there is any shortage of US citizen tech grads. Many say that many of our citizen grads cannot find jobs in the tech fields. People supporting Trump due to his stance on immigration will not like this, and he might we be proven totally wrong in the near future.
And I don't think anyone has the authority to just start allowing all those grads to stay in the US and work. They'd have to ignore the law as Obama does and hope to get away with it.
I support Trump as much as anyone, but he will hurt himself with this because it is totally inconsistent with his overall stances on immigration.