Xbox, I find myself in agreement with you on most things, but I see this one a bit differently.
So far in 2015, San Diego has added 4,800 jobs per month on average. So even if 4k people get laid off from qcom, that’s less than 1 month’s job growth. And that assumes that none of these people will find other jobs in San Diego, which is of course not the case. Given the general state of the tech industry as I see it (which is: techies are in high demand), I would be surprised if even half of the people had to move out of town. Let’s say 40% have to leave — now we are down to about 1 week’s worth of San Diego job growth to replace those folks.
So I just don’t see this as being a big issue for San Diego housing as a whole. It’s a big city.
That said, I could see there being an impact in the surrounding areas that are popular among QCOMers. If enough people need to move, there could be a bit of a mini-glut in that area for a while. But I would view that more as an opportunity for people who are looking to buy in those areas — not as a game changer for the overall housing market.