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Keep in mind that economists don't rely on a theory of supply and demand; they rather use them as tools. The concepts of supply and demand are ways of viewing the world. The allow economists to group different forces or causes into two different categories, in order to think clearly and systematically about changes in the world and how they will impact market prices.

Because supply and demand are conceptual tools, not an empirical theory, there will never be evidence that demonstrates that "supply and demand" is somehow false. What might happen is that future economists decide that "supply and demand" is no longer the most useful approach to thinking about prices. For now, virtually all practicing economists use supply and demand to explain market prices, because superior tools have yet to be discovered.