V2 failed not because of the STR formula that made efford of old players much less. It failed because of the battle mechanics that required tons of time - it was a genre change (to a step by step flash game) for the game and much less people wanted to play it.
Of course there are multiple factors that make some impact on population dynamics, yes there were a lot of multies, perhaps more then now, but there were much more real players as well. And definitely one of the thinks that contributes towards the ongoing player count decline is that some countries are wiped out from the map without any chance to return - decline of player count is a direct result of imbalanced domination of some countries. It makes BBs useless and impossible