BIP148 is brilliant because it ups the stakes for miners. Previously, miners could just choose to mine SegWit or legacy chain transactions with no consequence other than Reddit/Twitter storms. Now, miners ultimately need to decide if they want to split Bitcoin and risk tanking the value. Unless miners have been taken over by a malicious actor, like a country attempting to destroy Bitcoin, it would absolutely be in their best economic interest to avoid a chain split. Either way, Bitcoin without SegWit will not be stopped; it can only be temporarily slowed. I predict that Bitcoin with SegWit and without a hard fork will emerge from this like a zombie honey badger Phoenix, it will be stronger than ever, and all of the brilliant scaling solutions beyond SegWit will be rapidly adopted.