It is true. Northwest Denver ain't what it used to be. That includes the good and the bad.
As a white guy who grew up on the the northside, I have to admit that the white people in the Highlands/Berkely areas don't want to talk to me much either. So I can imagine how it is for the chicanos that are from there.
The sad thing is that the old chicano northsiders are some of the best people in Denver (and can be pretty damn funny too). But unfortunately, many yuppy/hipster types really only feel comfortable with their own kind.
If you are moving into northwest Denver and you moved in next to some mexicans, consider yourself lucky. They are going to teach you how the real Denver is - and it is a beautiful thing. .