Notice how these categories are all negative categories. They define themselves by what they're not: Supernatural means "related to the universe, but not merely the natural aspects of it", transcendental means "related to language or categories, but not merely referring to something material nor pure abstraction", spiritual means "related to what goes on inside of man, but not merely cognition or psychology".

They also imply that the speaker thinks of them positively, similar to how when you say "freedom fighter" you mean the same thing as someone else might mean when saying "terrorist", but you're saying that you think of them positively.

A materialist atheist thinks of all the things that might fall under the categories of the supernatural, transcendental, or spiritual as dumb superstition, while a religious person views them as useful planes of meaning-making and useful ways of motivating behaviour.

So, having thus defined "religion", maybe this is the way you would define "philosophy", and if you tell me how you would define "philosophy", maybe I might respond by saying "hey, that too kind of sounds like religion to me". This kind of debate would be neither original, nor surprising within the history of intellectual discourse, nor useful in any way.

The more fruitful debate is to be had around this: Why is this even such a hot-button issue? It seems to me like there are a lot of overtly religious people out there who are associated with the established religions, who are just unbelievably bad at it. They use these religious planes of meaning-making and religious ways of motivating behaviour to the effect of adopting insanely stupid beliefs and engaging in insanely counterproductive behaviours. As a result "religious" has become an insult.

If you go to a small town poetry slam, you're likely to hear some very bad poetry. But if you think this is what defines poetry, you would be mistaken. And if you never sought out poetry again in your life after coming across a particularly bad poet, you would miss out big time.

Finally, to close the loop to my other comment about how the rise and fall of religion is kind of cyclical in human experience: You can't ever get rid of the religious element in yourself, so the most productive thing you can do is get good at it. You can't ever get rid of the religious element in society, so the most productive thing you can do is get society to be good at it. -- The more you try to outright deny the religious in society (or yourself), the more it will re-emerge in transformed and hard-to-recognize ways and lead to regression where society is (or you are) just as religious as it was before, but it became less capable of doing religion well.