Any law that promises to protect all sincere believers also keeps the right to refuse protection to groups it finds uncivilized or illiberal. So courts must sort good religion from bad, orthodoxy from heresy, while denying that this is what they are doing. No principled basis exists for drawing that line.
Because officials will not admit that religion cannot be fairly defined, the law piles up roundabout phrasings and polite pretenses to cover the gap. The central pretense is that religion can be regulated without ever being defined. These workarounds cannot hide the absence of any solid reasoning underneath.
A legal guarantee of religious freedom needs to know what counts as religion, but people hold endlessly different and contested ideas of what religion is. With no shared definition, the law cannot coherently protect it. Judges and lawyers tend to be puzzled and annoyed when this is pointed out.
Many believers practice a do-it-yourself faith, deciding for themselves what their religion requires, free of church authority. Such everyday practice, like putting a cross on a loved one's grave, is mixed up with family, culture, and politics. That makes it hard for a law built around official doctrine to recognize and protect it.
Religious freedom began as a political idea that pushed toward tolerance. Once it becomes a legal test for which practices deserve protection, it becomes a way to exclude. The idea that once widened acceptance ends up narrowing it.