I would agree, but there are two problems here. The first is that the reasonableness test is really well litigated and will work in this situation, but it basically then buys the change in justification for the small business corporation rules in the first place, and says that they're intended to provide educational funding, retirement plans, and so on.
The second thing is that the reasonableness test will no doubt reflect the existing nearly 28% income gap between what women are reasonably considered to earn on average in this society versus men. It would build in a lot of gender differences in a very unintended way, in a way that is still being litigated in the courts today with respect to people being hired to work in unincorporated businesses.