Technically that is not true.

JR's Model Match feature, adds an ID to transmitted packets that uniquely identifies each configuration to the RX.

The RX is "bound" to the TX and the model memory, but the TX doesn't care what RX you use for this.

If the binding were bi-directional as you indicated, then it would be difficult to use multiple RX's on the same plane... something that works fine btw... without any unusual binding...