We shall not see the $100 coin again. We might see the $400 coin for some time, but not too long.
Yeah we have left the $100 mark and we will not see it back unless the halving comes in play or the price just drops. Unless one of those things is happening we wont see the $100 ever again.
The price of bitcoin will drop from time to time but it will not be going to $100 the halving is said to have effect on bitcoin and will increase its price so i doubt that we will be going to a $100 were bitcoin price is moving upward.