I know a lot of people have already mentioned this, but I truly think that Victor can't see in low lighting/the dark without the aid of his visor.
The parasite he implanted into himself has slowly degraded and altered his body, giving him similar characteristics to snakes. This has to include snake-like vision at night, because he clearly didn't get any heat-seeking characteristics like pit vipers have to hunt in the dark.
His eyes look normal still, not slit like a viper's would be either, so he most likely mutated characteristics closer to the types of snakes that are forced to use scents and vibrations at night because their eye sight is so bad in the dark.
If this is truly the case, then Victor most likely made his visor to help him see in the dark much more clearly. With how he looks now, I suspect he avoids going out into the city during the day. He likes to remain covert, and night is usually the best time for this.
That and he has a tendency to be ten steps ahead of everyone but his late master, Spencer.
Seeing in the dark while other's stumble around blindly gets that predator drive in him going full tilt.
I also noticed the computer he has in the visor, most likely some form of AI to help him visually analyze things more quickly like it seemed to do when he was scanning the t-virus infection site on Leon's neck
So victor uses his visor for a number of things
probably because he got so tired of being unable to find glasses in his office when he had to review medical documents from his staff at the Chronic Care Center lmao
