I was pretty sceptical at first since I read that the option was supposed to really work for people in CPU bound situations, however, it has significantly increased my performance!
I have a pretty high-end setup: 5950x, 32GB 3600 MHz RAM, the game is on a SSD that gets 5000MB/s Read with 4400MB/s write, and an RTX 3080.
I have at least double the performance now. All my settings maxed out and run ESO at 2560x1440; in highly congested areas I was only getting 40-60 fps, now I get 100+ frequently staying at my cap of 144 (again in a congested area like the crafting area in Alinor or Vulkhel Guard, in pretty much every other area I'm at my cap). This is with about 20 addons, Daybreak, and reShade as well.
I just wanted to say thanks because the performance was one of the things that really bothered me about ESO and it has now been fixed (for me at least)!
Has multi-threaded rendering worked out for anyone else? What were your specs and gains? Does it cause any issues with anything that you've seen?