I would reply to that question with another question. Why would you not comply with the request? I would not want to attract any attention toward myself and be forced to challenge the "requested is not mandatory" argument.
In the eyes of many people, every time you take off you are attracting unwanted attention.
So let's say you are making a series of photo flights. Or maybe you want to fly low and slow because, you know, in this country
you can. Whatever your purpose, whether commercial or pleasure, one is not required to officially state their reason for engaging in such.
Ok, moving beyond the platitudes...there is the thing commonly known as common sense. Just because we can does not make it a good idea. Just because something is legal does not make it safe. However, I do not think the answer can be reduced to a simple, "I must comply with the expressed request."
To comply may be a good thing (for the reasons you stated) but that should be left up to each PIC. Which comes to the point as found in the FARs. The PIC has final authority. As that is found in codified Fed regulations, the state is subservient. There are plane watchers up and down the CA coast. They are mostly non-paid volunteers and a few of them have a real Barney Fife complex where they want to be the one to bust a pilot.
With that said, I generally conduct my flights in full compliance with the requests. However if I wish to dip down and circle a land feature or such thing, I will. Let them bring their case.
On a recent flight I made multiple low alt passes of Pt Arena light house. I violated no state or fed rule or reg although I'm pretty sure someone thinks I must had. Perhaps in that example is my answer to your provocative question: the state reg is open to interpretation. Maybe one day the state will seek a test case to provide precedence to the reg. What I mean is, there has not yet been a legal case to find the reg is capable of being upheld and is as of now only a request.
Still, referring back to my post a few days ago, I think the change from prohibited to a less restrictive notice as shown on the sectional chart is due to a legal case. I need to research that to see if that is the actuallity.