Not that it makes him any less opposed to same-sex marriage, but I think 'vocal' is very much not the right word here. The only quotes I can find from him on the subject are him saying he's not going to talk about it.
Basically, we got played, Eich made a private political action, someone used that to get rid of him and then Firefox starting paying 10x as much to their CEO, doing all sorts of anti-user stuff, acting in advertiser's favour (but not too overtly), and ultimately ditching their engineers so they could maintain the CEOs stupid pay. All while begging users for money.