Old-Fashioned
We all have a different image of what a marriage should look like. In the past, men and women had very clear and distinct roles in a marriage; the wife was the housewife who was meant to clean and cook and take care of the babies while the husband is out at work, earning the big bucks.
These roles and conventions changed over time, and while most people are grateful for that change, as now women have more autonomy and power (in a marriage and in general), some people still believe in those old values. We can see why this woman finds this tweet disturbing, though- it pretty much goes against the tremendous progress that women have made over the years.