If your team holds 2 points in sPvP, then holding on to what you have is a winning strategy, although guarding an uncontested point can cost you in score. (See https://forum-en.gw2archive.eu/forum/pvp/pvp/Not-much-glory-from-defending-a-point/first#post214162 for more detail.)
Perhaps there could be some score awarded for guarding a point even if it’s not being attacked?
But warning — you have to be extremely careful about this. SWTOR awards points for defending a node, and has a warzone in which point farmers often decide to sit at the node and concede the game. It’s very frustrating to be in a PuG in which two or more teammates decide to give up but not leave.
Perhaps only award a point for defense if the team is not trailing in points controlled, and only when a node is guarded by a single player.