The other problem in my mind is that there simply aren't a bunch of highly standardized smartphones for sale without an OS of some sort already installed on it. It's not like the computer market at all, where you can buy "blank" computers and or really easily wipe some crapware OS install.

Manufacturing hardware is stupid expensive and smartphones are really refined at this point. All the players with the capacity to make high-quality phones are already committed to their OS for all kinds of monetization strategy reasons and Firefox OS wasn't offering anything to them.

Between users, devices, manufacturers and carriers, Firefox OS's only chance was to commit to a 10-20 year plan and fund continuous development until it was so good it was obvious that it needed to start ending up on real mass consumer devices.