I may be many things to many people. I may be a pariah to those whose faith in BTC is tenuous enough to be threatened by what I have to say. But one thing I am not is dishonest -- at least not intentionally dishonest -- to bitcointalk.org.
Let's say your clonecoin takes over. It gains majority hash power, in a permanent and convincing way. There is no chance that segwit will ever regain dominance.
How would this play out? How would the millions of bitcoiners around the world, most of which know nothing of this power struggle, react, to the newly established fact that their bitcoins are no longer bitcoins?
Probably by making an evaluation of whether they want to stay with the segwit chain or exchange into the cash chain. If this indeed comes to pass, it is not going to happen overnight. People will have the chance to mentally (and fiscally) prepare. It is not as if their current holdings would stop working. After all, segwit will still be segwit. No exchanges, vendors, payment processors, retailers or other entities that accept segwit will suddenly stop taking segwit. I think the apocalypse you imagine is just that - imaginary.
And you really think most bitcoiners know nothing of this controversy? Really? Even ignorant wall street pundits have been talking about it - for months.
OTOH, I can picture two things that would be apocalyptic: either some totally unrelated coin usurps bitcoin's rightful place at the top of the heap; or, the miners eventually take advantage of segwit's inherent ever-increasing incentive to roll back segwit and claim the anyonecanspends as their own.
What does it matter? We have a plethora of wallets to choose from today. There is no sign that future wallet development has halted. I imagine at some point multi-currency wallets will become widespread, though this would just be gravy. And indeed, many serious bitcoiners (even plenty of pikers) have multiple wallets already. What problem do you envision the wallet ecosystem causing in a flippening environment?
I think that would be dependent upon how fast such a postulated flippening might occur. If gradual, probably very little effect. If overnight, it may be traumatic. Either way, not nearly as severe as if some other crypto usurps bitcoin's rightful dominance, or if segwit fails.
Probably more germane is what stunting ongoing future adoption can do to the future of cryptocurrency as a whole. This is a persistent yet mostly unseen and unmeasurable drain on our path to monetarily freeing the world.
'Only one chance'. How magnanimous of you.