Startups are having massive layoffs right now, and each week bring companies further and further down the chain lay people off. I strongly suspect we'll see more major layoffs next week.
Most big tech companies are driven by either consumer spending and advertising. Before 2008 at lot of these companies still had not capture their full market share, so even in a recession there was room for growth. Now profits in these companies are based on market dominance. Even the big names will likely take a hit as the severity of this recession starts to take hold.
Finally in the Bay Area there's the looming problem that huge amounts of everything is paid for in RSUs (restricted stock units). The more ridiculous those total compensation packages may seem to outsiders the more they are built up from RSUs. In theory you should just live off base salary and RSU are the (very thick) icing on the cake, but this is unrealistic in SV. This stock part of the compensation goes a long way to paying for the insane housing in that region. Stocks drop and instantly Bay area income does to.
Tech will be effected, but a combination of naiveté and denial make conversations here seem like tech is safe.