A prenup would cover all of this. You don't see rich and famous people in court much, do you, for family reasons? Because their spouses know that if they try to play games with the court system then they get nothing. So, fine, accuse me of abuse - take the children through lies. You're right, there's nothing I can do stop it (in the short term) but if a spouse were to take that drastic action and they were cut off from the will, from a steady income, from a car, etc. they would live a painful life. Hopefully this threat, or the consequences afterwards, would wake them up.
A prenup is not going to prevent marital discord, or resentment, or divorce, but it can bring order and justice to an otherwise disordered and unjust legal system. Your real-life examples continue to prove that i'd rather have a prenup than not have one. At least I would have some defense in a 'worst case' scenario.