Only if the property protected by the pre-nup becomes mingled in the marriage. You can't use a prenup to retain full ownership of the house you both live in, for example. It becomes community property.
You can only use a prenup to protect separate holdings that are never used in the marriage.
Only if your community property state has a specific law.
This is NOT true otherwise.
Prenups CAN and DO get drafted which envision living in the same house.
They even have provisions which say that if the house is sold, the PROCEEDS are still subject to the prenup.
living in the house is not really relevant if properly drafted.
I don't agree with your conclusions of law. What becomes community property in community property state, is what is generated from your personal services after you are married. I don't know if that can be reversed by a prenuptial agreement.