Just guessing here, but maybe it caused problems for the Ground Control personel, who might be used to identifying ariplanes by glancing at their tails. Having every BA plane with a different tail paintjob would thus cause some confusion.
I seem to remember that American Airlines went to unpainted planes (except for trim) to reduce weight and therfore reduce fuel costs. This was before fuel economy was a fashion or an overriding factor. Therefore, the “silver” AA planes. Othere than that, white was the most practical color.
I remember criticism from pilots and controllers who found it very difficult to identify BA planes with the ‘ethnic’ tailfins - it is after all usual practice to have a very distinctive company design painted on the tail. However, not being involved in the industry, it could all have been media BS for all I know.
IIRC, white was used on the British V-bomber force to help protect against the flash of a nuclear device going off below.
A real laugh flying for the V-bomber force, to compensate for blinding nuclear flashes, the RAF came up with the following scheme. The pilot would fly with one eyepatch and the co-pilot behind a blind over the canopy. When blinded the pilot would remove the eyepatch and fly until completely blind, then the co-pilot would remove the blind and wear an eyepatch, flying until blind himself :dubious: and :eek: