Not really, because Concorde died in the seventies when the lie flat business seat didn't exist.

BA and AF managed to keep the zombie fleet going very profitably all the way until the end in the early 2000s, and that business wasn't killed by the lie flat business class seat either. It was killed by the impossibility of continuing to operate a tiny fleet of '60s planes forever.

Now if you said that the reason we don't have ANY supersonic passenger jets today is because lie flat business seats are good enough, then that's a more defendable position, but I'd still say that the overland flight restrictions limiting any SST to just a couple of routes is a bigger factor.

When I flew on Concorde the one thought I never had was "I wish I had a lie flat seat and half the airspeed".