Yeah, I figured someone would say that. The parasites change them all. Wait. Nope. Not really. They just change a select few like Drow sensitivity to sun. Hmm...
And they never state this. So if my Drow suddenly doesn't have sensitivity to sun, why doesn't she say, "Wait. Somethings off. I am standing in full sunlight and it doesn't effect me."
Nah. Not buying it.
Maybe the line is not implemented yet?
Astarion does have a line saying something extremely similar, it's not in game yet either but will probably be when the companions become playable characters. No reason why they couldn't add a similar line for the PC Drow characters?
You are right though! Not knowing much about DnD, I started a Drow character and had no idea Drow were supposed to be sensitive to sunlight until other NPCs started making surprised comments such as "a Drow? in the sun?" and I went to google it...