I am old enough to remember when the "This is not BG3 but DOS3" started. It was about an hour before the gameplay reveal, when Stadias youtube channel was spammed with "THIS IS DOS3" over and over and over.
An hour before anyone had seen any gameplay at all.
D:OS 3 images were leaked early, so everybody pretty much knew that "Baldur's Gate 3" is a D:OS 2 clone right then. This was simply confirmed during the presentation.
Fans just wanted a proper sequel to Baldur's Gate 2, but they are getting a sequel to Divinity: Original Sin 2 instead. That said, you shouldn't be surprised to see so many upset BG fans.
