"Sure, power users can be a pain in the ass, but if everything were up to casual users, we'd all still be on IE 1x, i.e."
How true. To paraphrase Henry Ford, if HTML5 developers asked instead what casual users wanted, we would now have a faster Flash.
It's history repeating itself over and over: developers and power users introduce or ask for something innovative, then casual users notice it, embrace it but also ask for it to be simpler to use ("50 knobs are too many, we want it to be usable with 3!"), therefore many functions are automated, other removed and interfaces are dumbed down to make the product palatable to the lowest denominator; however now the product has lost most of its "cool factor", not to mention some advanced functions, and doesn't attract power users anymore, many of them ending up migrating elsewhere. Rinse, repeat.
That is not going to happen to Firefox, since the war for conquering casual users has already been fought and won by Google thanks to their pervasive advertising telling everyone the lie that Chrome is better and safer. Mozilla should instead focus on giving power users the best possible product wrt security and privacy, two aspects where it would win hands down against Google, while at the same time try not to lose those among casual users who happen to be concerned about privacy and security and to whom Chrome would not be an option.
As for Mozilla's need to become profitable, why don't they attempt to use their widely known brand to sell personalized Pi-Hole-like boxes, hardware firewalls, VPN bricks that connect together from here to there, etc. Imagine two boxes with network plus audio ports: you connect mic, headphones, optional camera, a network cable, your laptop and the two boxes will establish an authentic E2E encrypted voice + video + data communication from anywhere to anywhere, no other operations required. Mozilla could surely provide the necessary services to get around NATted or filtered connections, and the shiny boxes with their logo would ease the association between the brand and the concept of private communications, security, privacy etc. helping as a consequence the adoption of Firefox as well. I think if they really want to focus on privacy and security they shouldn't ignore the hardware field where their brand can still make a difference.