[flowingfocus]

Yes, our models are never complete. As someone here already wrote: "all models are wrong, some are useful".

What makes me optimistic here is that since the enlightenment we have a good track record with arriving at better and better models. In the language of David Deutsch: We are arriving at better and better explanations, where the quality of an explanation is determined by rigidity ("how hard it is to vary") and reach ("in how many situations does it apply"). His books "The Fabric of Reality" is a great book by the way, he describes how the theories of evolution, quantum physics, epistemology and the theory of computation are connected with each other. The bit about good explanations is from "The Beginning of Infinity", also a very good read.

[sampo]

From 1954 to 1975, theoretical physics created the standard model of particle physics. Experimental verification of the theory continued through 1980s and 1990s, and finally the Higgs boson in 2011.

But if we follow the dictionary definition of scientific theory "A coherent statement or set of ideas that explains observed facts or phenomena and correctly predicts new facts or phenomena not previously observed" or "a hypothesis confirmed by observation, experiment etc.", then after the 1970s, theoretical physics about the fundamental building block of reality hasn't really been theoretical physics, but rather hypothetical physics. They have worked on lots of theories (or rather: hypotheses) that they have not been able to test and verify experimentally.