2 years from now when E3 roles around, the vast majority of the people saying that they are not going to buy these consoles are going to be arguing over what is better, Halo 5 or Uncharted 4. You are not going to sit out 10 years of gaming because of second hand games or always on consoles. You are going to buy a console and change your habits.
The industry is changing and we all need to adapt. On the PC, many games need an always on connection and when it comes to your mobile gaming, you can't get your apps without going online. As for the people saying that the if the internet goes down, you can't play your game is bad. Guess what? When my cable goes down, I can't watch TV. Not much difference. If I want to watch my blu rays and the power goes out, I can't watch them either.
As for the used games argument it may keep some people out from buying hardware but in the long run they will come around when the system price drops. Besides, I wouldn't be surprised if MS allows you to buy used media but you have to pay a fee to activate the game when you install it like an online pass. For them it's a win win as they don't have to pay for the physical media charge to get a second customer.