Maybe that's just Roll20?
It works great on Foundry. And probably on the newer Unity Fantasy Grounds.
I know I got burnt out on Roll20 a few years ago, it was a PITA to do prep for and didn't feel worth the effort. But other VTTs are superior nowadays... I don't know if Roll20 has done their long-promised big revamp yet.
But to the point, some characters having darkvision on a vtt just results in everyone wishing that they'd picked something with darkvision, and me as the GM feeling like the non-darkvision players are missing out because some players are seeing content the others aren't.
Player with 120ft darkvision: "Oh wow look at that gross pit, what the hell is that thing?"
Human: "what're you talking about?"
If it's in combat, maybe the human player will see the pit in half an hour

I end up throwing some little lights up here and there so the player doesn't feel left out.