As I had encountered that day by day more people are joining bitcoin inspite of its sky rocketing price and day by day more and more government and other agencies are coming against bitcoin so will bitcoin stay alive and will it be able to invite new user in the network?
You said it as bitcoin was some kind of Ponzi scheme where old users need to invite new blood because network will collapse otherwise.
Bitcoin is not a trap for anyone, it is a choice, if you think it won't be good investing in BTC, then just buy and support it.
People are suddenly waking up when price is over $1000, saying "but it is too much for me to buy" but it is only a beginning.
With limited number of coins, deflation will hit us, making our coins much more valuable.