The warning on the barrel was placed there over 20 years ago. There were no laws on the books in California that required any such warnings back then. I'm not sure there are now.
The magazine disconnects also predate any laws in California. The Browning Hi=Power has had them for decades as well as some S&W semis. Some law enforcement agencies used to mandate them for their officers and so S&W installed them on many of their semis many years back. Nothing to do with Califas.
Thumb activated safeties have been on semis for over 100 years.
If you want to get in a shoot out with California politicos fine with me, but shoot straight at least. It's a matter of pride.