Using a single engine fighter as a photo reconnaissance (PR) plane is only a good idea from the speed point of view. Were there extra Spitfires about?
If the Supermarine fans at the Air Ministry couldn't accept the Westland Whirlwind as a fighter it would probably have made a very good PR plane.
The Mosquito was another private venture plane like the Whirlwind that the Air Minister and RAF high command seem to have accepted only reluctantly when war and sheer performance made it impossible for them to refuse.
The Mosquito had similar speed to the Whirlwind, but being a proper bomber, to use the Mossies as PR planes didn't make much sense unless they weren't needed as bombers - which was never the case.
But the Whirlwind had so many enemies they pulled them all from service and scrapped them even while the war was still on! (1943)
Even Dowding seems to have had some animus against them as he sent them all up to Scotland for the Battle of Britain, despite being faster than Spitifires and with four 20mm cannon when the Spitfire and Hurricane had none.
Erhardt Milch and no doubt a few others greatly feared the Mosquito would be used in large numbers. Feared because it was almost too fast to catch, could bomb at low level with much greater accuracy and only had a two man crew.
But Bomber Harris & Co. had their lovely Lancs by then and weren't letting go of them; some things are more important than just winning wars you know.