The claim is that the greenish space makes dark objects appear more easily, and I know the “realism/fidelity” claims were clownishly wrong considering the space-fascist future features hand carts (that you have to buy with real world money!) and a star system loaded with 90s malls with hot dog stands, but something about making space itself a soupy greenish is… well… 
seems like they could have just made the ships less dark to see them more easily since you know actual space ships are usually white anyway.
tbh I don’t even hate the look but I also don’t care about realism
I wouldn’t mind the greenish space at all and I wouldn’t even mock it if it weren’t for the big spending true believers declaring how much “fidelity” Star Citizen has and how “realistic” it all is and how “no shortcuts are taken” in the so-called simulation.
I mean they could also just make the ships, stations or whatever they think needs to be visible just look as if they had a light source on them, you know, like classic space games did.