Even if the fees will be 1/2 or even 1/4 from what they are now they would still be too high for daily usage. Imagine you would have to pay 5-10 bucks every time you buy something with your credit card. I don't think Segwit and LN would decrease the fees to less than 1 USD, so even if bitcoin sustains, there is surely a room of alts to take over in areas where using BTC will simply not be worth it.