That is one side of the coin. My impression of the other side of the coin (we really need women perspective on these to be honest) is women should be happy to be stay at home moms and just raise kids etc. and a segment of those that do try to live up to that loose their self identity and all sorts of negative fallout comes with that.
One size does not fit all. Some women want to stay at home, some don't. Some men don't mind supporting a wife never working (on the extreme end) and some have a problem with it. Some folks live in areas that are more accommodating to a single income from an average job, some areas you'll be in poverty.
You're right that one size does not fit all. However, to clarify, my comment was mostly directed to my understanding of the poster's wife wanting to stay home but FEELING like she wouldn't be contributing to the household and FEELING like a burden. My point is that I think that feeling for her is likely one that has been created by our postfeminist and heavily individualized culture.
I don't think you would say these women aren't contributing to the family or to society. It's just that the contribution isn't strictly monetary. However, I don't think there is a way to argue that society has not greatly influenced the perception to be that monetary contributions are the foremost goal, earning money not as a means to an end, but as the end in and of itself. Thus, the natural assumption of some (not all) is that 'stay at home moms' are "falling short" of everything they could be. I think the narrative is that women can have it all, give 100% attention to her children AND to work and that one does not feel the impact of the other. That's obviously not true. It's not true for men either. You can't be in two places at once (side note, I also reference the portion of my comment about how many families had family trades and worked together all day, providing for both the financial and spiritual/emotional health. Unfortunately, this is not possible for most people now). Now, It's a sliding scale of where your time, energy, and goals are. It's all choices and priorities.
I certainly have my opinion on what is healthier for the family given the current state of things, but Like you said, we must all choose what you think is best for your own family. My suggestion is to a husband whose wife wants to stay home but she feels like she would be a burden, and it's simply to tell her that she IS contributing in a way that could not possibly be hired out to a daycare service.
Personally, I can't imagine my wife wanting to be fully invested in our children's upbringing by staying home, being able to make it work financially, but telling her 'No' just because I have some vague problem with being the only one "working". Not that that is you, but some guys do think that way and I just don't understand it. I think that goes back to money not being a tool or means to an end but being the end in and of itself but I don't know.