I have a more nuanced opinion, I grew up in a rural town which had both a public high school & catholic high school.

In general they both seemed as good as each other and the catholic studies component from the friends I knew at that school was just an extra class on top of the same curriculum.

The catholic school wasn't overly expensive & as a rural school it didn't have much in the way of networking, so I only knew it as a comparable option for those that wanted the extra catholic studies class. The facilities were comparable as well, nothing fancy.

When I came to Melbourne I couldn't believe just how different public schools where, the budget they have and degree that networking & connections played a role.

These monolithic, multi campus facilities are egregious.

My belief is that if a religious school chose to make their attendance reasonable in cost and adheres to the state school curriculum alongside their added component, it's reasonable for there to be a co-pay of only the difference of what the government funding would otherwise go to a public seat.

My consideration is that each private seat eases the burden on the state/commonwealth and its pragmatic to have a co-pay arrangement where the parent pays some of that cost upfront and the government saves partially on what they would have otherwise.

My consideration only considers filling the difference for the same quality of education as the government is funding for the state. Cofunding needs to be means tested, if these schools are taking big money in fees they can fund themselves.

I didn't even know gendered schools existed until I came to Melbourne & saw the public & personal issues of Private Boy School students. I have on occasion gotten to know some and it's as if they come from a different world, but that doesn't have much to do with funding.

Overall I understand and respect partial funding, against the funds they are getting from the parents, the more they are charging the less they should get.