On the contrary, the gamma seems to be more properly applied now, and the default brightness will have the dragon almost invisible in a properly calibrated screen.
It makes perfect sense why a poorly calibrated screen required them to turn the brightness all the way up in events. Also, I tried setting brightness to 10 just to check it, and it looks worse compared to default brightness than vanilla DS looked at 10 brightness. Probably related to how their lighting works.
Usually in Souls games I'd recommend people to just ignore what the brightness slider settings said and either leave it on default or setting it to 4, but I'm pretty sure this game's brightness settings should be set according to what the screen shows you.
I honestly think it looks great, but as you probably recall, I was already sold on it since the DF video, so I'm not the best metric for you.
You don't play on PC, though, right? If you did, you could always just test it yourself and get a refund before 2 hours of playtime if you don't like it.