Why do you assume he "needs" her to support his career? Many founders are deliberately single and not in a relationship to focus on their startup, and do perfectly fine.
And how could you call someone a "servant-wife" just for choosing to be a stay-at-home mother? In what universe is that not completely disrespectful to people who choose to be stay-at-home mothers? You are calling a person a "servant" for being a mother and denying her agency by defining her only in relation to her spouse.
By this implication, the opposite of a "servant-wife" is a "working-wife," and it's shocking that you can't define a person independently of a spouse within this framework. The term "mother" doesn't do this, but better yet, it's best to skip negatively judging strangers entirely.