If you bailed out after WP8, you missed the really tragic one. Windows Mobile 10 changed everything again (and had the gall to call the new one 'Universal' apps), and they missed their target of all the wp8 phones being upgradable to wm10, and for those that were upgradable, the OS was awful for the first year, and Edge was a worse experience than Mobile IE (which says a lot).

Oh, and they decided to only target the high end of the market, instead of a full range, so they lost the low end market that was selling a lot of phones in poorer nations.

/rant of a dedicated windows phone enthusiast.

At least firefox lets me put the urlbar at the bottom now! And Android picked up dark mode from WP as well.