Yeah, just a symbol until your deceased partner's family tries to take your house. Just a symbol until you realize you can't sponsor your foreign partner for immigration because the government doesn't recognize your relationship.
Those legal protections around property are the whole point of the law recognizing marriage.
At the time, same sex couples already had the right to marry in California. He donated money to take that right away from them. Would your stance be the same if he donated money to remove civil rights protections for racial minorities?