It shouldn't be that surprising that Trump is doing exactly what he said he would do when he ran from office. Trump hasn't banned immigration, he has just dialed it back. Even Obama had similar immigration quotas for his first several years in office. It's not that far of a deviation from what's normal.
President Trump will not back off his travel ban. Yes, it was right for him to amend the travel ban as to not affect United States green card holders. However, Trump is still responsible for our national security. He has an interests in ensuring that we know who is coming to America.
Not only was this one of his more ignorant and arrogant non-thinking moments, I'm also guessing he never thought of how this would affect Americas who are traveling abroad. Does he not think other countries have people who react like his followers. This is just the tip of the iceberg.
Donald Trump is way too stubborn to admit that he is wrong. Even if he is proven to be wrong about something, he refuses to acknowledge it. On the rare occasion that he does admit that he was wrong about something, he frames it in a way that makes it seem like he was right, and other people were wrong. Therefore, if he ever does give up on the immigration ban, he will probably find a way to blame someone else for it.