In Pacific Rim, Trespasser laid waste to the SF Bay Area. When do you think they began to rebuild?
Not until after the movie. The SF Exclusion Zone was a Chernobyl-type situation for a while (though some of the hardier among the displaced did try to cling to its margins in hopes of returning). That’s why building the Jaegers was so important. It was proving almost impossible to bring a kaiju down without variously compromising the long term habitability of these major population centers.