It's common and acceptable to refer to a nobody who's not shown their claim to fame in terms of another famous, impactful person who happens to be their spouse, sibling, etc.
If you don't understand how referring to someone solely based on their relationship with another person is denigrating, particularly when trying to highlight your perception of them being incompetent, I'm not sure what to say to you.
After reading the thread, I am still unsure what makes her a proper candidate to the board seat, but I might know that's she has more claim than her husband to it.
I am in a discussion about referring to people as 'spouse of x'. They're not the same conversations and I am not sure why you would expect the contents to be the same.