I thought the tweet was fine - there are many legal, fine Mexican citizens. In addition, Mr. Trump’s desire to enforce the laws of the land includes ALL illegals. It just happens that many of them are Mexican.
His statement was certainly reminiscent of "I don't hate blacks. Some of my best friends are black". Such statements were never considered to be "playing this game at a higher level".
There's also the Treaty of Guadalupe Hidalgo (1848), which ended the Mexican-American war and resulted in a lot of Mexican citizens gaining American citizenship. What's more interesting is that these old families tend to really dislike the new immigrants.
It just happens that many of them are Mexican.
That's quite true, but what's surprising is the number of OTM (other than Mexican) illegals there are: the result of Mexico facilitating the Central and South Americans traveling into the US.