And they really shouldn't. If you're not pissing off your power users you're not moving fast enough. The only user-stories that mass-market browser makers should care about are casual users browsing the web and software developers publishing to to the web.
Power users are a completely different market segment and have totally different needs and expectations from causal users.
This "strategy" will only drive the few remaining users away who actively decided to use Firefox while not winning any new "casual users" over (because those don't care about what differentiates Firefox from Chrome or Safari, they're all just web browsers after all).
But they're not moving fast enough, unfortunately. That's why there are a lot of new features available on Chrome that are not on Firefox, and that matters a lot for normal users because for them it's the browser that's broken, not the website.
The other day my mother asked me to check her pc for problems, while at it I was like
"...let me remove Chrome and install Firefox"
-"Don't do that" she said
-"Why?!" I was surprised because she is old and not technical at all, why would she even know what a Firefox is... Or have such strong opinion
-"Just don't do it, I don't like it"
-"Ok, I'll leave Chrome and you can try both"
-"Won't that use more space?"
-"Not really a problem as long you don't open both at same time"
-"Don't do it I have already tried it" and more or less ended there, but I am still curious why
Maybe I should explain her that now it is different because they have colors ways....
(with fast internet, low ram, and still HDD, I thought that Firefox with disk, and memory, cache disabled would be best)