Okay. I suspect you and your players don’t play in a way that’s conducive to Ravenloft.
My players wouldn’t fireball a group of farmers on a hunch. They just don’t play that way. Therefore that very cynical outcome wouldn’t work. The fear that any group could be bestial murderers wouldn’t cause them to fireball everyone - though it might cause them to suspect everyone. The scene also followed on from a relatively secure scene in the Blue Water inn with Van Richten, which may have contributed to them taking the scene at face value.
If your only fear of Strahd is that he might kill you, then you need to work harder. My female bard player was mainly concerned that she would be dominated and bitten.
Zombies are fine. Ravenloft zombies that don’t stop moving even after you’ve chopped them up are a different matter. When the zombie’s arm you just chopped off crawls along the floor and starts inching up the door towards the latch to let the others in then it may be different.
Ravenloft is NOT for everyone. Then again neither is Darksun or Planescape. It’s just one them of campaign that resonates with a lot of people.
The problem is, if everyone complains that it’s not their favourite setting that gets published then it just generates a lot of negativity... and guess what, campaign settings become less likely to happen.
Everyone will get their flavor eventually. I just understand why they chose Ravenloft first.