Samsung had this for years and people are generally uninterested. I love the thought to have the _possibility_ of plugging the phone in a USB-C dock and everything works, but honestly, I have done this... like, zero+1 times. For those times I'd need my proper desktop OS, and mobile apps / file handling etc. are just inferior.
Well unlike Samsung, Apple has a great user friendly “proper” desktop environment they could teach their mobile devices to run. Plug iPhone into a USB-C monitor and get a full macOS computer and I’d have no complaints.
Now, they never will because it just doesn’t seem like their style to give users more capabilities on iOS/iPadOS devices. Even if they put the macOS stuff in a container or VM so there’s a strong security boundary.