As I said, now, I am actually all for this, especially in the TA, but numbers are more after war than during war. And not always the case based on country. Commercial and private fields at this point may have but military airbases didn't really need them for the same reasons people are arguing against the idea here. Just like we may say in game, RL sticks were ordered to land SW, E, in some crazy CAGs cases, sometime V....... (Vertical)

Because runways have numbers just like our planes have skins.
You fly don't you? That's a reference to FAA or NTSB standards of the present day. This English field, currently may be closed but there is no painted over numbers.... Even today's paints and surface painting techniques, you will see the "old" markings.

the X means the runway is closed.
Burtonwood Field, UK - 1956

Henderson Field, Guadalcanal - 1959
Mareeba Field, AUS - (Circa WWII)

It does look to have RAF markings

it's not a B-24. If I'm right, that's a Avro Lincoln