I think one crucial issue in this thread here is that people compare Starbase, a (primarily) 1st person sci-fi Sandbox-MMO, to traditional MMORPGs with the occasional sandbox elements.
Last I checked, Starbase wasn't declared as an MMORPG. In fact, there's no actual RPG element in Starbase. No progression, no levels, no character stats, no classes, rpg-typical gear, skills or anything like that. Since we lack the typical RPG features, I don't see why Starbase would need the RPG-typical 'treadmill'.
As a sandbox-game, players should come into the game with the expecations of a sandbox. Create your content yourself.
I'd argue if you come into the game expecting a treadmill, you were looking for a different game and misjudged what Starbase is trying to offer.
Though I also understand and agree with the underyling problem that is stated here. Especially for new players, but overall as well, there isn't really any gameplay loops that allow you to actively play the game outside the deeper sandbox experience. There still isn't really anything particular to do, nothing to guide you through the game. No missions, no active combat, nothing in particular to progress along.
The game is no different to you after 1000 hours than when you first started it up.
The starter jobs were originally a good means to compensate for this lack of orientation and destination a typical MMO(RPG) would give you.
But they've been made redundant and serve no other purpose than act as the in-game tutorial. Personally, I feel even the dev-factions have moved away from the 'get in and play' playstyle they were created for.
Though at the same time, I think fixing this issue is also outside the scope of the game. It simply is the nature of a sandbox game, and practically all of the solutions for this problem would require NPC interactions in various ways. And that's simply not what Starbase does, on the contrary, it is supposed to be a game without NPC interaction, active progression, and ultimately, a treadmill.
I would be open to a discussion about how to compensate for the lack of a treadmill though rather than creating one. I think it would do well to give players orientation where it's possible and fits in with the rest of the game.