Since you divide by a higher pressure, obviously you get a lower displacement L.

As the Imperial unit gives the rated capacity (in 95 cf, for example) at certain rated pressure. They go hand-in-hand and must be used together.

The moment you raise the pressure, the rated capacity is no longer the same (at 95 cf). It should increased.

In Metric unit, the L is the equivalent water displacement of the tank. So multiplying by pressure gives you the internal gas capacity.

For example, there are 7L with 200 bar tanks, and also 7L with 223 bar tanks available. The external size of these 2 tanks are the same and should displace the same amount of water when submerged.