There are many reasons to believe a theory may not be forthcoming, or that if it is available may not be useful.
For instance, we do not have consensus on what a theory should accomplish - should it provide convergence bounds/capability bounds? Should it predict optimal parameter counts/shapes? Should it allow more efficient calculation of optimal weights? Does it need to do these tasks in linear time?
Even materials science in metals is still cycling through theoretical models after thousands of years of making steel and other alloys.
For instance, we do not have consensus on what a theory should accomplish - should it provide convergence bounds/capability bounds? Should it predict optimal parameter counts/shapes? Should it allow more efficient calculation of optimal weights? Does it need to do these tasks in linear time?
Even materials science in metals is still cycling through theoretical models after thousands of years of making steel and other alloys.