Maybe it can be thought of as a tooling problem?
Say, a plugin that allows a one-click publish code + data from Matlab, and then it all goes up on a well-indexed page so that others can download/run it.
The idea isn't to ask researchers to formalize what they make more than before, but to include fully reproducible details in the publication. A spreadsheet is totally fine because you can see how it works, reproduce the result, and tweak the inputs/methods to build on it.