I find it strange that people simultaneously argue
"Faith schools are wrong/dangerous/bad and it's not fair they exist"
And
"How dare they potentially prevent my child from going there"
Faith schools - on the whole - get good results. There seems to be a correlation between the "faith" aspect of the school and the results. Parents should be able to choose an education that matches the values they have for their child. Eg many feel uncomfortable with the government guidance on trans issues/whatever else, and wish that when their child is being taught, they have the faith side of things put forward as well as the standard secular side.
Sometimes on MN I feel like atheists think religion is a hobby to be left at home. It underpins someone's entire worldview, values etc. they are going to want their child to be raised with those values (+ if good parents, a healthy exposure to other beliefs too).
You can't raise children in a vacuum. A secular/atheist state school isn't a "neutral" environment. It teaches just as much about worldview, values etc as a faith school.