It does-
H.R Giger defined it.
It's an phallic-headed gaunt- chitinous "man" with a tail, always.
Beautiful and elegant in its own way, as Giger would say.
We've seen some fantastic deviances from the original design, with those basic tenant's in mind.
The Big Chap, Isolation Alien, The Runner, The Labyrinth Alien design, The 'Protomorph" Alien.
And absolute garbage when they aren't adhered to.
The AVPR PredAlien, The AVP & AVPR Alien.
Nearly every "Hybrid" in the comics.
The Neomorph is the one exception, thanks to Carlos Huante.
& That essentially kept the same ideas, swapped the smoke stacks for spikes.
Phallic head for pointed head, biomechanical skin for a translucent humanoid skin.
Inner jaw, for the deep sea- real life equivalent. Pharyngeal jaw.
The fact that it's the stipped down most basic, beastial version of the Alien we know is why-
the design works so well, it reflects what it is functionally. The most basic version of the Alien.