Interesting also that "native" UK women (or men) who stay home to look after families are "contributors", while newcomer women (or men) who stay home to look after families are leeches on the system.
I've been looking around on other immigration type forums-
According to the DWP staff on the welfare forums, next year the UK are closing the loophole where a single parent works, but one parent of a couple doesn't work and that couple also claim the welfare benefit called Universal Credit. Described on there as - no more being a housewife/husband unless you can afford it; that on Universal Credit there is only jobseekers unless they are exempt.
Interestingly, I put the figure 37k into a welfare calculator and based on two children, they can still have some Universal Credit (just). I assume that £38,700 is too much to be able to have any Universal Credit.
They also said that "light touch" where the other parent only worked part-time and in doing so avoided having to go the job centre, was ending. That all those on "light touch" would be going to the job centre unless they worked full-time.
As those on a spouse visa can refuse to work and instead indirectly claim Universal Credit via their spouse who can claim benefits, once they have ILR they will then be subject to work requirements as a Settled person in the UK is.