I think the potential of TSR2 has been vastly overstated, not least by its chief test pilot who hung his hat on it instead of on Concorde. He thought Concorde would be cancelled and TSR2 would be built, but he backed the wrong horse.
Also, UK couldn't just cancel Concorde as Julian Amery had had written into the 1962 Anglo French agreement a binding clause which meant cancellation would require both Britain and France to agree to that.
By getting Concorde for 27 glorious years of M2 transatlantic flight (3 hour flight time!) when USA and USSR tried and failed to do the same was IMO a far better legacy for UK than a military aeroplane of dubious promise.
Oh, and BA did NOT get them for £1.