I personally switched from Chrome to Firefox, but I think we need more well running browsers, not less. Even most well-meaning organizations get many have strange ideas and can use "my way or the highway" liberally when competition does not produce other palatable options. Thus while I did switch I hope Google steps back from this heavy handed approach (and more valid options get developed by other groups and companies). My 2c.
We do need more well-running browsers, which means browsers with roughly equal market share. I'm not comfortable with an 80/20 situation, but even then I'd prefer Firefox to be the 80 instead of Chrome.
I would also prefer an 80/20 split to be in the Firefox favor.
However, I do not see that "many well-running" means "roughly equal market share". Browsers are software and thus easy to replicate. And due to the huge market (> 1B users), even 1% market penetration is meaningful -- that is provides enough users to stay alive and develop.
Linux, text editors, many email clients, etc. were originally hackers toys, not grandma's tools and as such had a small (but vocal and dedicated) user base that cared about functionality and not market penetration. But once certain functionality threshold has been reached a lot of people were willing to wrap the core in a grandma-style interface. It could work for new browsers, too -- the main threat is not low user base, but being eaten by a large corp once it is capable enough to be a potential threat. My 2c.
