Tyranids are supposed to be infinitely adaptable, so why do we keep seeing the same bioforms over and over again?

I love the Tyranids as a concept. They are probably one of the most fascinating factions in 40k because they are basically a galaxy-spanning superorganism, constantly evolving, adapting to new environments and creating whatever organisms they need to consume a world.

But I feel like there is a huge disconnect between what Tyranids are supposed to be in the lore and what we actually see most of the time.

We keep seeing the same classic bioforms, gaunts, Tyranid Warriors, Genestealers, Hive Tyrants, Carnifexes, Neurothropes, etc. And most of the time, the only differences are the weapons they carry, their size, or the color scheme of their Hive Fleet. I understand why this exists from a tabletop perspective, since armies need recognizable units and models need to be produced, but outside of that, especially in artwork and stories, I feel like we rarely see the truly alien and almost limitless adaptability that makes Tyranids so interesting.

I would love to see Tyranid organisms that are completely specialized for different environments, like massive aquatic creatures hunting in the oceans of consumed planets, Tyranid lifeforms drifting through space and attacking ships directly, organisms adapted to gas giants that absorb their atmosphere and use it as a resource, Tyranid "plants" spreading across worlds or space and harvesting energy from stars through photosynthesis or radiation, microscopic Tyranid bacteria, parasites, fungal networks and countless other forms of life.

The terrifying thing about the Tyranids shouldn't only be that they have bigger monsters than everyone else. It should be that they are an alien ecosystem capable of creating any possible form of life needed for survival.

Instead, they often feel like we are only seeing different versions of the same evolutionary path, basically variations of gaunts that go bigger, more armored and more specialized, rather than an entire alien biosphere that has evolved over millions of worlds. All of them have the same claws, the same face and teeth etc...

Maybe I'm wrong and there are examples I haven't seen, but I really wish we got more of that side of the Tyranids, the truly weird, unpredictable and almost incomprehensible biological horror aspect of them.