We sort of expected that to be the case from the start. The PC versions of the last three games were graphically superior to their console counterparts with higher quality visuals and PhysX support. This is the bar that was set for these games and this is what we had every reason to expect. WB simply fell well short of the goal here. As for expectations about fixes, I don't think those are unreasonable either. I don't think they forgot to add the visuals to the PC version. It seems more likely that something is broken in the game that's not giving us these visuals or has them disabled.
Even Metro Last Light was able to pull solid/stable mid to high 40's, with most of the settings cranked up on my 780. And visuals on that game was insanely, crazy good.
And in that game, when my fps dropped, i was happy. I was happy that Metro was giving a good workout to my graphics card, and it showed. The Russians did a magnificent job on the port. Something WB/RS even with a tremendous budget could never even accomplish.
When your fps drops in Arkham Knight, i just want to find the nearest baseball bat and go bat-shit