Externally speaking Starfleet ships march to the beats of NACA/NASA X-planes, Klingon embrace a very soviet yet alien look in contrast, Vulcans look advanced and sleek yet ancient and mythical with the biggest pointiest toys on the block.
Internally speaking construction is depicted as having limits, tech and interfaces are familiar to real world, cramped ship like rooms are the norm, and there’s no handwaving over how everything might fit inside the ships.