There's an enormous gulf between opposing anti-LGBTQ teachings/practices and being anti-Christian. For one thing, equating the two presumes that anti-LBGTQ teachings are definitional to Christianity. That's plainly false. Some Christian denominations have drawn a line in the sand over gay and transgender issues, but many have not.

Some major denominations don't make it a big deal, while others actually are fully affirming.

People claiming that this is a religious liberty issue are actually making the implicit argument that religious people should be free from criticism of their religious beliefs, even when those beliefs impact society in important ways.

The football club acted because they don't subscribe to the notion that religious beliefs should off limits in public discourse. They did not fire that CEO because he's a Christian. They fired him because he's an anti-LGBTQ bigot whose religious beliefs must not insulate him from the consequences of his bigotry.