According to the article, it came to a head late last year, around October IIRC, that's when it started being fully enforced. So, I would imagine initially it didn't make a huge impact while things were still somewhat shut down or just coming back online. But now that more of the world is back to being open for business, the logjam built up pretty quickly.
Another CA specific issue that relates to all of this is how independent contractors are no longer allowed in CA. So a trucking company has to hire drivers on as employees, paying all the employment taxes, rather than simply paying them a straight rate as independent contractors. Companies did not want the extra employees or taxes & regulations which go with them, so let go a bunch of drivers who were previously independent contractors.
This is a very tough state to do business in if you are a small business. It is that way by design, the big players own our legislature and pay for legislation that makes it near impossible for small operators to compete. All in the name of social justice, environment, equality, etc.
I deal with it in my personal business and it is brutal.