Respectfully, for you and other people who may be confused, this is a bad take.

The Satanic Temple is not an organization that believes in a supernatural Satan, but one that uses him as a symbol in the rebellion against authority. I, of course, am assuming that you think "dying on a hill" for Satanists is inherently wrong.

I would also argue that if you believe in the principals of the Constitution it is important to stand up for them especially when you disagree with the side whose rights are being infringed. There is the old chestnut of protecting the speech you don't like, which applies here.

Finally, you are wrong about the legal issue. The Equal Access Act of 1984 prohibits public secondary schools that receive federal funding from denying equal access to extracurricular clubs, including religious clubs, based on the content of their speech. You have to let all religious clubs or none. The district already opened the door to religious organizations, they can't close it behind them.