This law was written to give code enforcement a cudgel against unlicensed repair shops. All the auto enthusiast blogs and forums immediately lost their minds, but there hasn't been a sweep of the neighborhoods with officers asking to look inside of your garage for uncommon tools. The one complaint I could find online [1] was from a dude whose handle was "nimblemotorsports" and he said he had a car lift on his property (but it hadn't been set up yet). [2]
There's plenty of room for grousing about poorly written laws, but this law has lots of other equally poorly written laws across the country to keep it company. Sacramento county isn't forbidding you from putting shiny new headers on your hot rod in your own garage.
[1]: https://grassrootsmotorsports.com/forum/grm/it-illegal-do-ma...
[2]: It took only a little more effort using the nimblemotorsports name to get an idea of why his neighbors might completely reasonably be getting irritated enough to call code enforcement.