Yes that’s an issue I personally have. Like I said with monster races. When you build a certain narrative and your players go against it because they want to play whatever then you have to make concessions even if it breaks some of the immersion.
Drow would also not be welcome in the current scenario. If BG3 were tabletop and I were the DM, players who chose to play drow would be attacked and imprisoned. I think that reaction is more appropriate considering the current hostility.
I agree, they are too gullible - they should be more mistrustful and warily.
But their situation is desperate and they need every support, they can find. I think it's realistic, that they wouldn't be hostile, if they see, a drow or a goblinoid is slaughtering their enemys, without gaining an obvious advantage from it.
Edit: Goblinoids or Drows are no worgs or gnolls, and i assume that tieflings know the difference between them and monsters