In short, Google played a different game.
2) Nokia rose to power on simple cellphones. It was never a dominant player in smartphones. In fact smartphone was a wide open market with no dominant players when Apple entered that market. So Apple never needed to fight any incumbent.
3) Google still sells 10X more ads than facebook, so it's rather premature to say facebook has beaten google in ads. And even if that does happen eventually, it'd be because facebook avoided fighting google in search ads (unlike Microsoft tried to with Bing) but instead invented the new market of social ads & newsfeed ads. Once again it's the strategy of avoiding fighting the dominant incumbent in its own game and inventing a new game instead.
So it's really Google > Nokia (Symbian), Microsoft (Windows Mobile), Palm and RIM, with Apple off to the side somewhere. And the complex, multi-faceted Apple vs Google battle in mobile isn't an upstart vs an incumbent, it is a battle of two upstarts who have become the incumbents.
So Google never really defeated a dominant search engine - it merely took advantage of a giant vacuum in the market.
2)Apple - Apple never defeated Microsoft in the PC game. Instead it focused on emerging markets: ipod, iphone, ipad. Eventually these new products (smartphones & tablets) became powerful enough to erode the PC market. Even now Microsoft is still dominant in the PC market. It's just that PC is no longer where the action is at.
3)Facebook - there were no dominant players in social networking when facebook was founded. Myspace was the biggest player, but "big" was a relative term back then. Even at the height of its popularity the vast majority of the population was not Myspace users. Sure if you were 16 year old in 2004 then you were probably on Myspace. but outside of that demo Myspace was far from dominant. Most people were not on any social networks. In short it was a wide open market.
I'm sure there are examples where a challenger took on a dominant incumbent head on and won. But those are the edge cases. You pretty much need all the stars to align perfectly to have a chance. It's not a strategy I'd bet on.