I don’t doubt that some fathers go for 50/50 exclusively as
A) A CM elimination strategy
B) An anti asset loss strategy
C) An emotional donkey kick to the gut of the ex strategy
However there is also the reality that visitation hasn’t done the best job of keeping the bonds between father and child(ren) secure and solid.
With 50/50 both parents are more tightly locked into a location because of schools and travel time considerations. So it’s harder for one parent to unilaterally decide to move a considerable distance away. without taking into consideration the negatives they will have to take as part of the package. Few want to do a huge round trip for the school run half of the week for example.
Personal I don’t think 50/50 is optimal for children at any age and stage. It’s too easy for them to end up in a rootless, no real home, kind of life, especially if new partners and step/half siblings come into the picture. Nesting is probably the most child-friendly option for most of the kids, a lot of the time.
But little unites men and women onto the same page of “it’s a hard no from me” like that option.
So that leaves visitation or 50/50.
In cultures where the father is the de facto parent and mothers get variable levels of easily accessed visitation you’d see many women bite your hand off for 50/50. Not by any means a majority as a cost saving or “pay back time you bastard” measure. Just because a few days a week (at best) visitation doesn’t meet their emotional need due to their attachment to their children and they justifiably fear the fraying of the bonds with the small people they love the most.
I suspect many men, having watched the landscape of the 80s - 2010s play out as they grew up, have a strong interest in changing their task responsibilities in order to keep their children closely emotionally bonded to them.
Which may turn out to be no bad thing from the child’s perspective as they grow up, have children of their own, with a model of fatherly involvement that is a few steps above “see occasionally, mostly in McDonalds or the swimming pool, if at all”.
It has to be better than a landscape where the role of fatherhood for too many has become a “for now, but maybe not for long” role. Which causes more than few wounded children’s souls. And it might become less socially acceptable to walk away from your children if stepping up to the plate with the day to day grind of child rearing is seen as not just a perfectly reasonable option, but the expected behaviour of a “good/real” dad.