Is Starmade even a Survival game at all?
No food. No fuel. No ammo. Total invulnerability in your camp, and massive amounts of resources are super easy to acquire.
I'm not a huge survival buff, but I've spent some several dozen fun hours in survival games like Kobold Tribes and Don't Starve and in any one of those games, if I spawned in and was AFK for more than 2 minutes getting water and a snack, I would return and find my toon D E A D. In a survival game you must constantly, constantly take steps to survive, and the pace is usually very unrelenting.
In Starmade, you can spawn in and walk away forever and come back and still be alive. Tough challenge there. You can strand yourself on a planet and go AFK for hours and come back to find everything none the worse. Pirates aren't a threat - radar jammers cost nothing and can be fitted on your very first noob rocket at spawn and you'll never have to deal with them again. Invest a meager 15 minutes or so in mining and you can spawn a station, enter the build block, and have 100% invulnerability from everything forever. 15 minutes in and game over, if it's about survival. You have to fly into a sun or attack a pirate base to die. You literally cannot die from just doing nothing in most situations.
Maybe I'm missing the wider picture of what the gaming community considers to be "a survival game," but I see no survival challenge at all in Starmade.
I can't say what it "is" other than somewhat mold-breaking. It is Starmade, any other label is pretty arbitrary at this stage in its development. At it's heart it's just a voxel sandbox and is mostly about building and designing cool stuff. It's also a FPS with hundreds of weapons, various types of armor and shields, stealth, buffs/debuffs, and loads of different available composition builds and strategies as well as counter-strategies for almost all of them (i.e. a fleet composed to overwhelm with long-range offense can be mostly countered with a very strong point defense composition, bubble ships are countered by ionized siege weaponry, etc). With the addition of fleets, NPC factions, and improved trade it's starting to gain a lot of potential for RTS + 4X play.
Personally I think the best long-term potential for the game is to increase and enhance 4X, RTS/FPS and RP elements and capabilities all pretty much equally and go for a RP-4X game (instead of like a RP FPS/3PS as most RP games are) with fun RTS/FPS fleet battles for the combat side. You RP a company, empire, family, cult, alien species, federation of gravity wells, rabble alliance or whatever, get your 4X & RP on as that entity, and when you hit resistance or someone comes at you, you get your RTS & FPS on (at the same time, no less, since many players may choose to lead from HB, but humans are so much better than AI that leading from a fleet's capital ship and having teammates controlling other craft in the fleet as much as possible would certainly be more effective). That's what I would like to see.