It's definitely gotten worse in the North Park Blocks.  I was an avid Powell's Technical patron in the days I was a computer programmer and it was present, but not omnipresent.  These days it can be pretty bad.  At times, the parks are dominated by homeless, many young junkie travelers.  Public urination and defecation, drug use, and sex are common enough that I've seen them on multiple occasions.  Granted, I drive or walk by the area several times a week.