Well, I have a problem with that.
The first diver was probably a Mat Salleh, and they are notoriously known for their big noses with a high and defined bridge. In other words, a sharp nose. So that dude probably made a mask and that triangle part was made sharp and high - well, cos his nose is like that!
When he dons the mask on, that triangle part envelopes the nose nicely. It is shaped that way because it will then be easier for divers to pinch their nose and blowing into it to equalize the air space in our ears. I actually love equalizing my ears and hearing it go pop.
Thing is this - I am Chinese. And we aren't blessed with nose that stick up high in the air. Mine is as flat as a piece of squashed dumpling.
That is not to say that I've got a small nose. In my family, the big nose gene runs deep. But when I mean big, it's more wide than anything. And the bridge? Non-existent. Which explains why I have problems with specs and sunnies as they tend to slide off my nose.
So when you have a flat nose like mine, and a big piece of protruding triangular nose-area on the mask, your nose somehow gets lost in it.
I kid you not.
I had problems 'locating' my nose to give it a proper grip so that I can pinch and equalize my ears!