Actually it was a high priority.
The acceleration into standard combat tanks, 52/60/75/100 &150gal was bogged down with perception that self sealing and low priority materials (wood, plastic, paper) drove Mat.Cmd into a bureaucratic design, build protortype, test and re-design cy cle.
Further complicating the challenge was a real logistics issue of transporting high volume/low weight tanks via shipboard when tanks, aircraft, vehicles, POL were critical.
I agree your point about British not solving the problem. That said the RAF had no high-altitude daylight strategic aims and were content, to a degree with what we provided to augment those few instances.