I still have a hard time believing that they CAN'T do Day/Night. I don't believe anyone who says they can't.
As has been pointed out numerous times, even games in the 90s could day/night and have weather. Geez! Even side scrolling old Nintendo/Sega games had levels that suddenly went from sunny days to stormy dark nights.
Come on. You can't tell me they can't do it. It might be a pain, but they can do it.
And proof? They took the original cutscene with the crashing nautiloid and turned it from day to night. If they can do that, they can rework a day/night cycle.
Yes. It'd cost money and time and resources. Yes. It might not be worth it to some.
But it's worth it to many, and it's, as some have said, embarrassing that you have this "We're the have-all-be-all D&D 5e experience" game of 2023ish and yet NOT have day/night so something as basic as drow sun sensitivity and such actually exist like they should. Come on! It's kinda ridiculous. Solasta has it and their budget is so much lower. Pathfinder has it, and same. I get that graphics are way better for Larian's game here, but you can't tell me it can't be done.
That said, I will accept that day/night and weather COULD create limitations on low-end PCs, and so, in an effort to appeal to a wider audience, they are trying to make sure they don't tax the lower end PCs as much. That makes much more sense to me, especially for weather effects. Night? Yeah. I'm not sure that makes as much sense. I guess maybe more shadows could cause issues, but I have a hard time believing it'd actually be more taxing to have a darker landscape.