Very different games and very different expectations of effort spent. I've space trucked a lot in Elite, spending hours going back and fort. But it was never dull, more of a relaxing experience.

That comment stems from games failure to live up to its promises.

This game was marketed as an explorers game with 1000 planets to see, for example.

None of those planets have even the half of the content Skyrim/Fallout has. None of those planets are barren as Elite's planets, either. You can't traverse them more than 30 minutes, so it doesn't even scratch NMS itch. People that liked the exploration of any of those four games would dislike this games exploration very much.

The person above was probably expecting a more lively game, like any other Bethesda game and got whatever this is instead. It's completely justified to be disappointed.