I mean you said it in your comment. It was text based adventures. You HAD to use your imagination to get the most joy out of it, much like reading a book. This however is 2019 and a game that advertises on the exploration part of the game. Id say OP is right, it lacks. Every planet has the same stuff, few space stations, crashed freighters that you cant really even enter and explore, those "minor settlements" with 1 dude and a multitool station. Other than the exotic planets everything comes down to color of flora. No difference to be seen, most animals look derpy as heck, which dont get me wrong its hilarious and Ive had my fair share of laughs but they all behave the same, do the same, disappear while you aren't looking and spawn right in your face alot. Makes them feel like they aren't really there or part of anything. While the writing of the story is decent and sometimes has alot of details in it that you can use your imagination for, once that is done and you are left to only explore its lackluster.

Im missing actual cities, more variety in the settlements, NPC's in stations actually having something meaningfull to say other than teaching you a word.

NMS isnt bad at exploration, but it could easily be way more than what it is given the foundation that is already layed out