I understand yior frustration.
However, I think your thread is one of several that should be pinned to this board.
Too often on here, posters are advised to LTB and told that their ex will have to do parenting by themselves, will have to arrange childcare, will have to reduce their hobby, will have to buy stuff for the children to keep in their new home, will have to provide a home with enough bedrooms instead of the one bedroomed flat they might be planning on.
The reality is no man has to do any of these things.
Someone up thread said "Imagine if the OP provided that level of care, the DC would be in care."
Yes, that's true but the reality is mothers won't provide minimum care, will not walk away. That's why the old saying is a true one, women get left holding the baby.
Is that fair? No, of course not but that is the reality and I would advise everyone to bear that in mind and not get embroiled in some fantasy where the man has to do anything if he doesn't want to-apart from paying-because he doesn't have to and no-one can make him.
The other thing they can do-if they are paying a penny more than they need to-is stop paying a penny more than they need to,
Great if they pay up, stay involved but paying more than they need to and parenting is something they choose to do, not something they have to do,
I-and a great many others reading this-will know the truth of this from bitter experience.
So, OP, he's paying more. Tread carefully because they can and do stop this and as for him parenting, forget it.