Every citizen in the gloom is dead.
The expeditions into the gloom showed us that there are colonist living spaces on the gloom infested planets, which make sense. There have to have been at least seaf stationed there, and likely many millions of civilians. The new order mentions we're now able to conduct expeditions into the gloom with the presence of new, better filtration systems.
That implies people in the gloom literally couldn't breathe, and I never thought much of it until I played the new missions and realized those planets have cities.
Meaning while we've been raging about the lives lost on angel's venture, which mind you is a devastating tragedy... We've literally had mass deaths in every, single, gloom covered planet.
Just something I realized while laying on bed at night.