I just tested PTR and the performance is pretty bad. I’m on pretty decent specs and my recent FPS values were
1.35 (after the first fix): ~300FPS stable
1.36 (FPS JUMPS from 50 - 180) and game feels laggy and stuttering
1.36.1 Game is extermly laggy and stutterin
Reforged mode is not playable for me at all really.
Latest version 1.36.1.20631 is back to 300 FPS 
Thank you for tackling this.
It doesn’t seem like performance has improved on my PC at all.
Completely unresolved
Proof video on all versions of 1.36 low fps - Bug Report - Warcraft III: Reforged Forums (blizzard.com)