Honorable mention Battle Brothers, also long and it's really easy to avoid actual danger there.
I've compared Starsector to BB before (probably because I secretly wish Starsector took some more queues from BB). But I think the fundamental "problem" with viewing it as a rogue-lite and why it's ironman is destined to be a band-aid:
1) You can't actually lose the game
2) You have safe-haven storage and untouchable income in the form of colonies
3) You can avoid unwanted battles by using SP's.
4) You can accrue infinite money and by extension almost every ship in the game while completely avoiding combat/danger
Since it's pretty obvious that Starsector is a just a sandbox with the rogue aspect slapped on the side, people feel no qualms with saying "just dev-mod in more SP's" - and they aren't strictly wrong. The "optimal" rate of SP gain is dependent on the individual player, so debating what it "should" be in a sandbox game is a dead end.
Personally I would prefer Starsector be more roguelike, but it would require massive adjustments in virtually all areas of gameplay, including SP's.