You say this as if it is inevitable and innocuous. Would you also be so cavalier about it if the axis were not gender but physical or mental disability?
This is exactly the problem. If you're an engineer, you need to consider how your users might differ from you, or else your creation will be unusable, if not something worse. Nobody's asking engineers to make their creations universally equitable: that is obviously an infeasible goal most of the time. But they are asking us to try, or even consider it. Even in our comparatively enlightened times there have been many instances of the inexcusable ignorance engineers have shown in the design of their products. Here are just a few examples:
- https://gizmodo.com/why-cant-this-soap-dispenser-identify-da...
- https://www.nytimes.com/2018/02/09/technology/facial-recogni...
- https://www.wired.com/story/machines-taught-by-photos-learn-...
To be clear, when you were making your work bench at home, you were doing it in your personal life and not as an engineer, so I don't know if the same arguments might apply to that particular instance. But I do think you could have had a more thoughtful response to your wife.