in this particular case, i could imagine that in his role as partner as Basecamp there is a longer "credit trail" attributed to him just from a business operational standpoint beyond his joint family tax filing. that alone could explain the discrepancy between him and his wife beyond sexism.
By definition anecdotes prove nothing. Until there is statistically significant evidence of sexism this is just hearsay and your post gets close to slander.
In this case it will be absolutely trivial to check. Just feed in the same data for the same person only with the gender flipped.
While there may only be anecdotes at this point, there should be some investigation and discussion into whether bias may occur toward particular classes outside of explicit gender checks. Seems like that would be done by comparing the allowed limits with gender, race, etc. and considering why the algorithm may unnecessarily limit those classes on a broad scale.