Although the White Paper cancelled future manned interceptors it accepted that for some roles, such as transport, manned aircraft would be essential for a number of years to come. Hence the A400M being developed half a century after publication of the Paper.
Increasing interest in unmanned air vehicles to replace manned aircraft is analogous to the thinking behind the White Paper 50 years ago, when it was proposed to use missiles to carry out some of the tasks performed by combat aircraft.
Ironically, it was largely as a result of conforming to the Defence White Paper's requirement for projects to be managed by merged firms that TSR2 was cancelled. The 'shot gun marriage' of Vickers and English Electric led to inefficiencies and cost overruns.