Why not do some balancing on overperforming gear sets like Relequen?? Gear sets like this have CLEARLY defined the gap in performance between people that have it equipped and the ones that don't have it equipped.
ZoS does pay attention to SOME gear pieces. I don't know if you remember or not, but they balanced the skill when Maelstrom's bow buffed the fire ticks as well to do insane damage.
It is more minor nerfs to a massive number of skills, massive buffs to the greatest ESO meme skills (that themselves generally got nerfed to 5 years of irrelevancy for their OP sins in 2014), and a healing redesign. PVE dps is barely changing, ZOS is keeping an eye on the healing changes/rework, and it is week 1 of the PTS.
All that said... yes, those sets as well as CP and all the buffs to skills and light attacks and consumables etc etc etc all would need to be reverted to slay power creep.
zos will never touch op sets from last 1 or 2 patches otherwise nobody will do that content anymore (coudrest, brp, ecc).
Take time and in the future you'll se nerfs to requen, siroria and spell strat