There is definitely differences between the two game. But its hard to dispute the fact that the two games are really lacking in content and basically have variations in quests to collect things to advance the game and nothing more accept than promises of good things to come.
SoT and NMS both only progress with quest/ item hunting
SoT and NMS were both launched on promises of content more to come, and both have yet to deliver
Differences: one is single player offline in space where there is nothing to kill, just stuff to collect. The other is a co-op online pirate themed game where killing stuff gives you nothing, and you must do some task before collecting an item for a quest.
SoT game play can be broken down like this:
The first 5-10 hrs of game play are amazing, fun, exciting, and visually pleasing. After your first PvP battle, you probably have fun but then realize how much time you wasted without getting a damn thing.
The Next 10-40 hrs of game play you are probably enjoying the game still but getting tired of quest. You probably go to a skeleton fort or 2 and enjoy that unless you find your ship being attacked as soon as you start the event, because everyone else also wants to do the event for the bigger drops and hates the quests by now. So your stuck battling with other crews after defeating the skeleton fort, just to keep your loot and hopefully you make it to an out post and are able to turn them in without other players killing you and stealing your loot.
40+ hrs into game play, you have been to every island and now get upset when a quest makes you sail across the map to complete one. You have probably fought the Kraken and been disappointed in the effort vs loot drops. And you now avoid all PvP because it feels like a waste of time, unless you are bored or someone attacks your ship and you now have a vendetta to settle.
At some point you satisfaction with the game turns into thinking this game could be so much better, and wondering where is all the missing content. All you hear is that SoT is going to get content added in a couple months after launch. If you paid the $60 like myself, you find yourself wishing you just got the free game pass trial and saved your money to see if the developers deliver, or if its exactly the same as no man's sky. The first big patch doesn't seem like it really fixed or added anything, and now you wonder if the next patch will have anything at all that will make the game worth spending time grinding rep and saving up gold to make your char/ship look better.
One easy fix that would give the game a more well rounded feel would be to give a reward for killing something. A small amount of gold for killing a skeleton, snake, player, kraken or whatever. Doesn't need to be much, maybe 1-20 gold for a basic mob and maybe 100 gold for killing a player. But make it so PvP has a diminishing return on killing the same player or make it so killing the same player doesn't yield gold for a time period after he/she has been killed once.