ok suppose what you are saying is true and no one supports BCU, suppose by some miracle in few months majority of miners like whatever percentage value they have decided supports BCU then in that case bitcoin core developers must support BCU and BCU must be BTC or will there be a different excuse then.
Then BCU and BCC goes live everywhere and let the market decided, but don't forget Metcalfe's law, the two chains together will be worth less than one chain, a split will be bad for everyone.