The black bear population in California has been growing substantially in recent decades so one would expect them to show up in greater numbers and become more visible regardless of any other displacement pressures. So I’m not really sure what kind of point you’re trying to make here, or what suggestions you’re putting forward. Should we be hunting them more to bring down their population? Should people be moving out of 140 year old towns in foothill areas to open up more space for them, even though they aren’t native to the area? For now we’re co-existing peacefully in my area, and I’ll take that as a win.
https://wildlife.ca.gov/Conservation/Mammals/Black-Bear/Population