I believe there was a common denominator to the TSR2, AW681, P1154 and Fairy Rotodyne cancellations and that is the industry was out of control contractually as it was wedded to cost plus contracts (which were never going to make designers stop and think before they cracked on with some pet notion).
From my point of view I believe all these four projects were technically flawed although I do accept that the Government did not cancel them because of that.
TSR2 not enough wing, AW681 a VL transport just to take a P1154 engine into a field (why not a chopper?), P1154 silly exhaust gas temperatures and velocities preventing any operating site flexibility (to say nothing of immersing the fuselage and tail in said exhaust in conventional flight) while the Rotodyne was 'designed' to operate from a city centre (Hyde Park Corner and the Champs-Elysées) using a rotor driven by tip jets.
IMHO cost plus had a lot to answer for.