#7 an extreme minority care about being good at video games. aside from that cs/tf2 are easily approachable games.
fps is a played out genre that's been around for almost 20 years now. when you innovate a new genre and people love it, there's less people scattered across games.
the big difference between the 20 years ago is constantly producing lots of new content rather than making new titles every few years. each new title splits your community, making those sub-communities more likely to switch to a new game of the genre. This is why the old generation of fps games died off, but giants like wow continue to dominate the mmo market and league/dota will always dominate the team rts market despite games like titans/smite trying to ride the coatails and free money of a new genre.