The thing I can't get my head around is people who seem to think any criticism is due to them being a large family.
In modern times a family with 5 children is a large family. Families with 6 to 10 children is a very large family.
It's not something I've ever aspired to, but I do think if you are extremely well organised, work hard and have sufficient space plus the patience of a saint it is possible to parent even very large families to a high standard.
The thing is that this situation is a whole different order of magnitude.
When you get to a point you have to eat in shifts because there's not space for everyone to sit down to dinner, when the compromises being made include no assistance with homework/reading, no extra curricular activités, 3/4 children of vastly different ages sharing rooms, privacy and quiet places to study being forfeit then I think it's hard to argue that the overriding motivation is the joy of parenting children rather than the need/will/desire/financial benefit/media interest (or whatever it is that drives them) in simply producing them.
That fundamentally is what most people criticise - the desires of the parents overriding the needs of the children, a trait that something that if many supporters saw in other families (though manifested differently) would have little hesitation in defining as inappropriate.