Honestly, the time a server has been out barely affects it's player count and popularity, at least from what experience has shown me. If a server's theme and ideas are intriguing more players will migrate there. Granted it will take time for a grand Playerbase to be established, but 3 months at most should be enough. So if more servers are going multiplatform so be it, those that succeed will be determined by their theme, content and the interest they provoke in players. Not by the time given to them to sit around.