Children can make their minds up rationally about which religion they want to follow, if any, when they are old enough and have been educated about all the religions.
Indoctrinating them into a religion (cult), or even teaching them that one of the religions must be right, is totally immoral.
I can’t see any justification for people supporting faith schools and this indoctrination.
If we are to have schools that teach their pupils about all religions so that they can make their minds up later then having a faith school is a clear conflict of interest.