This notion of Concorde being old is as bizarre as suggesting we stop playing Vivaldi's Four Seasons because it first went into production nearly 300 years ago. In techonolgy terms it is as new as any supersonic transport and as a plane it is very young in its service life due to very low utilisation. It is thirsty and expensive to run but that's because it is half airliner; half spacecraft. It's flight deck is a bit 'classic' but functions as well as any glass version - just a touch more expensively.
Concorde is special for two reasons. Firstly other capitalist products can be removed and re-launched at will but Concorde is a unique product - across the whole world. Once lost it cannot be replaced.
Secondly we, the British taxpayers, forked out a shed-load of money. Someone ought to take care of that investment.