timppu: Unlikely. Unlike the first Homeworld game in GOG (and Steam), Emergence is not a remake of the old game, but it is the original, old, Homeworld Cataclysm game, only renamed.
So if the original Homeworld Cataclysm game (released in the year 2000) supported 1920x1080 (which it probably didn't). or someone has already made a hires/widescreen mod for the game and lets GOG use it free of charge, I don't see it happening.
But the game still works fine, yes? That's all that matters, everything else in this world is irrelevant.
The game works OK. It is just that I would benefit froma better resolution. Still, online, there seems to be a complicated workaround.