First, it's not clear or obvious that the 21% daily increase rate would increase indefinitely. Infection rate slows more people get infected, and new potential victims decrease.

Second, all regions saw giant, double digit growth rates at first, and then lower growth rates. Sweden is taking a more laissez faire approach, and their growth rate has dropped from over +20% d/d to +1% d/d [1]

There isn't data to support the idea that we'd have 100% utilization in the Bay Area without shelter in place.

[1] https://en.wikipedia.org/wiki/2020_coronavirus_pandemic_in_S...