The "truth" will probably be released mid-2060s onwards.
What could the earliest development of the TSR-2 do? Outpace a Lightning with minimal effort perhaps? Yes. Did the USSR have anything that could "out-intercept" the Lightning in the mid-1960s? No, IMHO. Did the TSR-2 therefore threaten to substantially alter the balance of power in Europe? Yes. Did the US fear that the USSR could copy TSR-2 tech? Undoubtably, which may or may not provide some validation for the destruction of the airframes.
Or was it just too expensive? We'll know all the answers by 2070
