I feel like this is way overblown but I think the logic here is that Mozilla claims to be an ally of privacy and internet freedom. While Google obviously, does not.
To add insult to injury I don't see an apology or anything similar from Mozilla (or callahad here on hn) that would show me they understand the extent of this issue - how badly they f* up on how many occasions.
It's ironic, right when browser can finally stand next to Chrome in terms of performance...