Drop frames in specific situations in pvp

Facing frost mages in pvp their spells all of them and specially frost wall drops my frames to 1~5, i cant lower settings anymore or i stop seeing important things on the ground with all the settings i never got to a midle term, some other classes this also happens but nothing like frost mages.
i have a rtx 2070 ti and it feels like cuz of wow i have to change it which aint a fun thing to do cuz grafics cards this days are expensive as hell… does any one have the same problem?!!

edit tested outside of valdraken with a friend with a frost mage WITH ALL THE MAX SETTINGS its super fine goes from 70 frames to 40 and frost wall to 20 but its manageable, but if i get inside a blitz or a SS and face a frost mage, uh dks my frames with their spells go so low as hell why shouldnt in a instance enviroment be less things to influence less textures less meshes less everything and how come its the place its worst i cant figure.

Another thing why outdoors the frames go to 100+ and inside cities goes to 30~40 auto its like its forced to be cap at those frames inside city walls why!!!

You don’t have to change GPUs because you are CPU-limited.
Judging by the age of your GPU i would asume you have something like a 2nd or 3rd gen Ryzen or an older Intel like 8 or 9k.

If you are on AM4, then you are lucky and should just swap in a 5700X3D and just double your FPS like that.

You don’t understand how this engine works.
Every player adds alot of calculations (buffs, debuffs, spells, WAs, combatlog etc. etc.).
All of this has to run on one main CPU-thread.
So the more players, the worse your FPS will get.
For example, it is not possible to always achieve at least 60 FPS on even the fastest CPU atm (9800X3D) in a 20man mythic or 30man raid.

Reducing addons and Weakauras to a minimum will help some but only to a certain degree.

The envrionments have a CPU cost too, but not much in these old zone BGs.
Not like DF or TWW zones, mesh density is lower.
Reducing draw distance will help though.
Not showing nameplates alone gives like 10-20 FPS in some cases.

Highest concentration of players and meshes.
Just log in at night when nobody is online and your FPS will skyrocket.