You can check out the actual sale prices of recently-sold homes on Zillow:

https://www.zillow.com/homes/recently_sold/house_type/

In the South Bay near Mountain View, there's basically no single-family homes under $1.5M, and the majority of houses go for $2M up. Many are in the $4M+ range. You can get cheaper in San Jose ($800K-ish for a run-down 2BR from the 50s) or Daly City (low millions), but most of the Peninsula and SF has a floor at a million.

Most Bay Area residents just don't own homes. They rent permanently or maybe own a condo. But the context for this sub-thread is "people with a house", and basically all mortgages for single-family homes are jumbo if you're not paying in cash or putting >50% down.