Actually, the main cause it failed was because Microsoft bullied the manufacturers until they said enough and bailed out. So they were forced to buy a manufacturer to keep going (Nokia) then gave up halfway through after buying it.

Microsoft has stupid amounts of cash and could have kept Windows Phone going indefinitely, even at a loss. It's how they broke into the console market, by keeping the Xbox going at a loss for a decade.

Yeah the lack of apps would have been a problem initially but everybody would have relented given enough time, and in the meantime most of the missing services could have been accessed in a browser.