How will the market value react to it, people wanting to sell bitcoin but there is no one to buy.
If people stop buying bitcoin, price will fall for sure because of the oversupply in the market. With the oversupply, sellers will be selling their bitcoin to the lowest price that every rare costumers wants. But talking about the usability, bitcoin will be more usable if the price is low because the fee would be lower in price value also. Bitcoin will be availabe again for small value payments.
But even though it would be more usable, people wouldn't want their funds to sink lower and lower so they will find another alternative that would make bitcoin die.