I don't see eth hitting $0 anytime soon anyway with all the activity in development and enterprise's getting on board, it's sure to bounce back in the near future
Today, even if governments accept ETH as illegal, the price will not be 0. Billions of money should be withdrawn. Why would you believe someone who thinks the price will be 0 without giving any reason? His only concern is not about ETH, but about the whole crypto world.