It makes sense. The first rain after an extended dry spell can be treacherous until the oils are washed off the pavement. Once it starts raining consistently in the winter, the roads go back to normal because modern tires have great traction on wet pavement.
Sure, but visibility is also impacted and is not something that improves with consistent rain. People should always adjust their driving style when it rains.
I grew up somewhere with 50" of rain/year and I can tell you folks do not change their driving style there either (until it's raining much more torrentially than it ever does in LA), so this phenomenon is not unique to LA.
