I didn’t say that it was being used to represent anyone, or that it was being stolen, I said that it was already in use. To use your examples, I’d think that using Pi or the degree symbol to represent the fediverse would be a bad idea too, as they could also lead to confusion. The semicolon is punctuation, so there’s less chance of confusion with that.

If an astronomy group made a poster with the three stars, would the stars be representing star clusters, or advertising that they’re on the fediverse? Given that the fediverse is still relatively small, is there more chance of the stars being seen as an astronomical symbol?