How do you know what would have been accomplished without that person's spouse managing the home? What if Jeff Bezos couldn't devote nearly as much time to Amazon if he had to take kids to appointments or be there when a contractor was at the house? And what if those diversions caused Amazon to be a flop? I would say that those contributions which were key to the success of the company absolutely do entitle you to 50%.
Now, I do think there's a legal argument to be made if that is clearly not the case, but a healthy person should have cut ties in that type of relationship before wealth was developed anyway. Presumably staying in the relationship after 25 years and after the accumulation of so much wealth meant that both parties were fine with an equal division of the assets.