Like many players, I noticed serious FPS drops in WoW Forever right after the last patch. The game ran fine for the first hour, then frame rates started dipping in raids and even in quiet zones.
After a week of testing I found a working combination: update the GPU driver, disable hardware-accelerated GPU scheduling, and lower shadows to Medium. That alone recovered about 15 FPS.
What actually solved it completely was following the WoW Forever FPS fix guide I found — it lists every step in order, including the registry-level tweaks that made the biggest difference for me.
If you are still struggling with frame drops after the patch, start there. The guide is updated for the November release client.