I believe it was Philip Dick who said that “Reality is that which, when you stop believing in it, doesn’t go away.”
Heisenberg, on the other hand, said: “…what we observe is not nature in itself but nature exposed to our method of questioning”.
Both of these suggest, I think rightly, that the concept of reality is metaphysical, rather than scientific. Ultimately all we can test is whether or not our ideas about reality accord with the answers we obtain when we carry out experiments.
I had not overlooked the bit you quote, but I was taking one thing at a time and trying to sort out if decoherence was linked to thermodynamics in such a way that would let us consider decoherence as a concrete feature in what we perceive as reality; or if it had to be thought of as some sort of quantum superposition of done and not done.
