I'm not sure. I think advocacy is a core part of its USP -- Mozilla is privacy-friendly, and that's an important point, especially as all internet users, even average consumers, are being constantly hit over the head by how data-hungry these huge corporations are.
It's an uphill battle, sure, and there are a lot of things to overcome, but I'm not so sure I'd blame the leadership on this entirely.
Mozilla is doomed when it's held to such an impossible standard (such as being "spyzilla" for supporting TLS PKI).
All this poo-pooing on Mozilla doing anything less than paranoid-extreme makes people leave for other browsers, which aren't any better, and often are way worse for privacy.
It's an uphill battle, sure, and there are a lot of things to overcome, but I'm not so sure I'd blame the leadership on this entirely.
I'd blame the market...for now.