I don't see how any of that is relevant.
The examples I gave are so definitively answered that we can derive the relevant laws mathematically, and prove that they must apply in all universes with the necessary properties. I've provided such a derivation in this comment: https://news.ycombinator.com/item?id=27336901
There are many other examples along these lines in science.
Even if scientists tomorrow decided that some variant of string theory is a more accurate model of the world than quantum field theory, it wouldn't affect these answers.
There's no aspect of the explanations of inverse square laws or conservation laws that have had their answer undermined by updates to a theory, or are less explanatory because we e.g. don't know the origin of all existence.
Science has definitively answered "why" questions in those cases, and many others.
This idea has been around for thousands of years and is similar to the central teaching of Advaita Vedanta. Indeed, we are continuing a truly great tradition of inquiry in our natural philosophy of science.
The point is that every update of a scientific theory shifts old "why" questions to new ones. Science will not ever and does not aim to provide an answer to the ultimate question of why anything exists at all or why a given theory of everything applies rather than another (indeed, string theory for example posits a possible, if not actual theory of everything).
In this sense, in the scientific study of consciousness, we do not aim for an ultimate account of why the laws of nature give rise to consciousness. Instead, it is about explaining a natural phenomenon within a theoretical framework that allows us to make predictions with respect to experimental outcomes.