I guess it depends on the cable geometry itself. But a hard and fast rule that shorter is absolutely better is incorrect.
@agisthos While that may be true for some or maybe most digital cables it is not the case for i2S that was designed originally for very short lengths to be used to make connections internally within a component. It was not designed to travel distance and the signal degrades rapidly with length and any cursory reading on the topic makes this limitation very clear — i2S is a different animal from the more typical SPDIF or AES/EBU connection. The experts I’ve read on the topic actually recommend a length of a foot or less for an i2S cable if possible.