I agree with your assessment of that neighborhood, but keep in mind that less than 10 mi. away are nice areas. I've lived the Crescenta Valley area for over thirty years and I like it.
Problem is, crime doesn't confine itself to little area bound by streets and blocks. Yeah, some neighborhoods are worse than others, but it spills over into nicer neighborhoods, and even nicer cities. I live about 15-20 miles outside of Johns area, to the north west completely outside of SFV, in another valley. We still deal with the BS that is SFV from time to time. And example would be I was at ny storage unit yesterday. As I was in the elevator on my way up, someone had tagged(scratched) into the paint inside the elevator "VSV" which is a local spin-off gang from SFV. We have to have a graphiti task force here in my town to get rid of it. They are REALLY good, usually removing or painting over it within less than 24 hours. But, they are busy people.