it does matter. I'm not sure if you are serious or not but whatever I'll elaborate
People tend to know that you can play destiny, battlefield, call of duty, etc on either console (Though Scrooge's point may stand that a lot of people might believe that the game [destiny] is hobbled on xbone). So they need a reason to buy whichever console. Graphics horsepower may sway some. Whichever there friends are on definitely matters. Then you add in the other games they can play. It becomes do you want to play gears/halo/forza the most, or one of a lot fucking more PS4 exclusives more. A lot of people could end up agreeing that battlefield, COD, and other shooters are already scratching the same itch as gears and halo, but on PS4 they can play bloodborne, need an action platformer for their kids like ratchet and clank, or a story driven adventure shooter like uncharted. Maybe they are even more off the beaten path and want to play a few japanese games like Tales Of (hey who knows, they couldve been fans of Symphonia back in the day)