Yes, I've seen it at Cosford many years ago and I remember being awestruck by the size of it - it is much bigger than I had imagined. The members of the Wilson government who are still alive should be hanging their heads in shame although Lord Mountbatten had something to do with it as I recall - I think he was CDS at the time
Had she reached squadron service there would have been probably: No F4s in RAF service in the strike role; No Buccaneers in RAF service; No Jaguars in the strike role; No Tornado. There certainly would have been no brief flirtation with the F-111 and AFVG. Britain would have built something else (better than the F4 and Tornado F3) to replace the lightning or, perhaps more likely, bought F15s from the US.
With the TSR2's range and likely payload, The RAF of the 1970s onwards to the end of the cold war would have been quite different and much more potent. That was probably the reason for its demise.
I wonder what name it would have had?