I expect Google to keep Mozilla/Firefox on the lifeline indefinitely to avoid antitrust issues in the states and EU, so Mozilla/Firefox won’t go anywhere.
Still, this doesn’t mean anything, because I often need Chrome or Safari to access some websites.
In the end it is quite funny: Moving a lot of stuff to the web made Linux a more realistic desktop option, at the same time to access a lot of stuff on the web one needs to run a Blink browser.
IMHO the most annoying thing is, that we could have at least some laws, which mandate that every government service must be available to Open Source users and every government paid software must run on at least Linux. Thanks to lobbying and power this will never happen.
Edit: To state it more clearly: Firefox is IMHO in bad shape and in a bad situation. Firefox won’t die, but at the same time right now I already need Chrome/Safari browsers, because Firefox support is broken on many sites. I see no way Firefox can gain significant market share, especially seeing what regular consumers tolerate from Microsoft/Edge and Google/Chrome.