Based on my subjective observations, homelessness definitely seems to have gotten worse in the South Bay Area in the past few years. If you go biking or walking along the various creek trails and railroad tracks you'll see more encampments. Some of them are fairly well hidden but if you stop and look you'll see the signs.

By the way, this is one of the reasons why it's tough to get people out of their cars and commuting by bike. Many people don't feel safe cycling through those areas.