"So what situation prevents any CA law enforcement officer from making an arrest in any CA county ?"
Nothing.
"If none then why have jurisdictions ? "
Well, I answered your original question about what the law is.
If you wish to challenge the law to have it changed to what you would prefer it to be, I suggest you contact representatives in the state legislature. If you want to debate your opinion of what the law should be, I'd suggest that this is not the proper forum for that.
We, here, are not the advocates of any law. We are merely trying to help people who need help to understand the laws that apply a little better.

