Edit: Oh and a fan HD remaster would probably be hard too, because Strike Commander has a mostly sprite based engine. Which is harder to get more resolution to then a 3D engine.
Strike Commander had a full 3D engine, in fact it was stupidly buggy and heavy to run on the PCs of the time (hell, it's still buggy now, I never finished the game because it tended to crash regularly on a mission for some reason).
The sprites are used for cutscenes and can easily be upscaled in all their pixelated glory.
Hmm ok, I've must have misremembered then, it's been ages since I've played SC, and I've never played it all that much. I thought it was much closer to Wing Commander 2 then 3, but apparently I was wrong.