It's.... kind of a lot to explain, but I'll try to give you a bit. And fair warning, while I have a lot of complaints about the game, I also think a lot of the common complaints about the game are often overblown or are down-right wrong.

So first off, in terms of gameplay, it plays like Skyrim or Fallout but with more polish, which makes sense since it's built in and running on the newer released update version of the same engine as those games. Personally I like the core gameplay of those games, so for me that's a win but a lot of people were upset that there wasn't some enormous leap and bound in terms of what the engine can do, as if studios like EA haven't been pumping out cookie-cutter formulaic entries of FPS or sports games with no innovation but I digress... The motion feels vastly smoother than Skyrim and the gunplay is an enormous upgrade over Fallout's; although there are some things to complain about in the combat, the actual physics, motion, and aiming are all solid. The perpetual nature of Bethesda universes at the scale and scope which they maintain the consistency continues to be impressive as hell, to me at least. If you haven't played Skyrim or one of the newer Fallouts, it's hard to articulate what sets them apart from other first-person RPGs, unfortunately, but in general I don't have many major complaints with the core gameplay.

The story and setting are really where my comment applies. So one common problem people mention a lot is that "Starfield is empty," which it is, but they almost always mean it the wrong way. People complain about how nearly every planet and moon is empty save for maybe a point of interest or two.... but space is almost completely empty. That's one of the the things Starfield does right, and the lonely empty feeling of walking across a barren alien planet just to be welcomed with the cold expanse of nothingness is one of the best parts of Starfield. But Starfield is way too empty, the problem is that's actually empty at the content-heavy parts. Due to story reasons Earth is uninhabited, so humanity has settled other planets... but each of the "main planets" has one city one it. ONE. Imagine if the whole of humanity's settlement of Earth was just New York City. That's absolute insanity. The idea that at least one or two of these planets wouldn't have developed into sprawling developing countries across the globe instantly shatters a lot of the logic of the universe, and it's this kind of big-picture-with-no-details thinking that seeps into everything in this game.

Another example is the shipbuilding, arguably one of the best and most well-received parts of the game. Without modding, you can't turn any ship component 90 degrees, and you can't even flip or invert many pieces. And when you build your ship, how the pieces actually connect (in terms of doors and hallways) is basically entirely by chance rather than being controllable or having logical rules. So you might think you've put together a great simple ship with a central hallway with doors along the walls on each side, only to find out that instead your ship is actually an snake-like disaster which requires you to go through every single room to get from the cockpit to the door.

There's just a lot of lack of attention to detail stuff like that, and lot of seemingly half-filled (if even that) space for content as mentioned above with the main planets. Beyond those flaws though, there are some really great concepts to play with, such as the need for physical information couriering because technology has figured out physical faster-than-light travel via the gravity drive but not how to transmit data faster than light without a physical ship with gravity drive to do it.

Also for Fallout to have an excellent in-game radio and for Starfield to not have a ship radio is an absolutely criminal omission.

Hopefully that answers it some? I dunno, ask me if you wanna know more I guess.