"Gay marriage" has nothing to do with OSS web browsers. 'tis a dark world where people cannot work toward common goals when their views on completely unrelated subjects differ.
I can tell you that, in the context of this hypothetical situation, any arguments that my actions are uncalled-for because "coffee has nothing to do with the Internet" would not have much impact on me.
We'll see how the promised inclusivity efforts go. If he's genuinely committed to inclusivity, great! For the moment, however, I have reservations.
This isn't about respecting beliefs, this is about the CEO of mozilla and if we can believe him and how his beliefs can and will affect the company.