I would not doubt for a second that new browsers without javascript, but using other languages, will start popping up in the future simply because of this.
It would definitely be hard. I actually love JavaScript. But I could easily imagine someone who has something against Brendan Eich start their own browser without javascript. And I can imagine it becoming viral, too.
The JVM, the CLR, Flash, NaCL -- all of these already exist with browser implementations yet are having traction issues.
On top of that, it is unlikely Eich controls JS to the same level as FF, so it'd be a mostly pointless gesture. It'd be like finding out John McCarthy was a vile person, and abandoning all LISP-like languages.
I think it would be like finding out if the CEO of Microsoft didn't want blacks to be able to get married. Would you expect blacks to continue using Windows?
Imagine you were gay. Would you want to use Firefox and JavaScript? I'm a big fan of JS. I'm straight and it's somewhat distasteful to me now. If I were gay, I think that feeling would be very strong.
I think it would be like blacks not using Windows because the CEO of Microsoft said that blacks should not be allowed to get married.
I believe users can boycott a product and start a movement and have a huge effect in today's world. It's happened before and I think it's possible it can happen again.
I think most people realize that it was socially acceptable for people to hold certain beliefs in another era and would not fault them for holding those beliefs.
If the car was invented by a homophobe, it's not like people would ditch it, given that cars are essential to many people and also given the time period the inventor lived in. But is Mozilla or javascript essential? Maybe. You could certainly be correct that it won't happen. But I can see it being replaced. I can see a group of people choosing alternatives.