I'm also a mathematician, and it doesn't bug me at all.

> nothing to do with spirituality

It clearly does have a lot to do with spirituality, for many people, as symbol. Much as the cross does for Christans. Neither of these symbols have spiritual meaning to me - a cross is just a cross, a spiral is just a spiral. I don't have much need for spiritual symbolism myself - when I meditate, I rather to focus on a simple sound or light source - but I'd consider it highly egotistical of myself if I was to start judging other people's use of symbols just because they don't understand maths, or whatever.

> fetishisation

I've yet to ever see this word used except to denigrate other people's beliefs, or as an attempt to make the user feel superior. I believe you did both here.

My advice, one mathematician to another: chill and let people have their symbols. Don't expect them to have a deep understanding of mathematics, much as we don't have a deep understanding of their need for spiritual symbolism. Nonetheless we can let each other be, and all get along.

Who knows, perhaps a fascination with this "sacred geometry" as they call it, might be a starting point for someone to have a genuine interest in mathematics.