I think the online influencer element of this really muddies the waters. It's largely fake, or maybe better to say, spin. Like all lifestyle influencers.
It's also muddied because there are some who consider anyone who talks about mothers and even homemaking as important, or the problems of needing two incomes, or is critical of the progressive feminist consensus (such as it is) on this, is a tradwife - I've seen Mary Harrington disparagingly referred to as a dangerous tradwife more than once.
I home educated my children for many years, and so have some long ties to some American homeschooling groups, and I became friends with many of the other women. Many are quite conservative and quite religious (though not necessarily evangelical.)
Even within that community, I don't think the "tradwife" thing as some describe it is common. There was a period, back in the 90s, when there was growth among certain patriarchal evangelical sects, and they had some influence in that culture. But they were considered dangerous and weird by many even in that conservative community, and they have been very much on the wane for many years.
Lots of people have said things upthread that are on the money, I think, so far as seeing mothering as important, the problems that come from the assumption that there will be two incomes, and so on. I think we all know that realistically, it can be very difficult to have only one income (which is why influencers want to monetize it all I suspect.) It's even harder in the UK compared to the US and region makes a difference too.
In my experience the economic bracket of most women who do this is husbands with a fairly standard middle class kind of income (though often they may be in trade rather than white collar work) but they live in a more lower middle class/working class lifestyle in terms of neighbourhood, vacations, cars, etc. They are taking a financial hit for the mother to stay home, but also generally feel it gives the whole family a better lifestyle - they tend not to put much value on things like yearly vacations, fancy neighbourhoods, etc. Wealthy families seem to be rarer than hen's teeth - they might have mums at home but it's not connected to a larger philosophy in my experience.
But while most I think accept that many don't have a real choice about working, I think there is also typically a strong view that as a society we should prioritize social models that allow families to make those choices. So that tends to inform their politics. So you won't see them, for example, supporting Swedish style daycare, because that tends to lock in two income families as necessary for any but the extremely wealthy. I think criticisms that it's unrealistic in the current economy kind of miss the point, to some degree it's about a practical criticism of that model and who it's really meant to be good for.