But what does "having principles" translate to? Focusing on the EME issue, how many people are going to be like "humpf, firefox added EME so I'm going to use chrome instead!"? Is that small slice of the user base even worth keeping? If they're going to be incensed by random issues like this, they're probably not worth the trouble to cater to, or maybe they'll just flip flop between chrome and firefox (depending on what the latest outrage headline is) that there's not much point in catering to.
If you can't articulate specific benefits to "having principles", then you're not really interested in firefox winning, you just want it to die a martyr.