People change too. You can't hold it against someone all their life because they donated $1000 to prop 8. For the rest of his life, people will look at Eich differently simply due to the small donation amount many decades ago.
If you're worried about his future career, I understand. But if he changes his mind he can equally talk about it with potential employers/partners. If he doesn't, then he gets to live with the consequences of his choices the same way someone who is out about their sexuality does.