To be honest, that in itself is probably worthy of notice. It is not a self-evident truth that all the laws of physics work exactly the same throughout the entire universe. There have, for example, been quite a few theories that have postulated that some of the fundamental constants may vary over space and/or time.
Therefore, just the confirmation that chemistry actually does seem work the same 11 billion years ago on the other side of the known universe is certainly not worthless knowledge. It may also have provided some knowledge about how long it takes for oxygen to accumulate in the evolution of a galaxy (though that may well have been known previously).
Furthermore, of course, it is a great verification of our observational capacity. Though the existence of water may not have been unexpected, our ability to observe it is quite something to marvel at, if I may say so.