You were saying, specifically, that the game was nerfed in 1.12, but when I proved you wrong you started to talk about other patches. Gotcha.and this is what i mean, you're not interested in educating yourself, you just wanna be snarky and hope you're right.
you're not.
EVERY SINGLE CLASS had been revamped between release and 1.12. talents were streamlined/improved/buffed and EVERY SINGLE CLASS got boosts to survivability and throughput. leveling had been streamlined with more flight points, mob pathing was a bit more contained with a few mixed in with the old paths (mobs used to roam about 5x as much which meant you were constantly pulling something else), gear stat budgets were bumped up a bit from 1-60 with level 50-60 gear getting an even larger bump. drop rates were modified for a ton of things too which increased the overall power level just due to the fact that better gear was more readily available
if you've been around at all you know that 6 months before a new expansion drops is "catch up" time and it's always been that way, this was the first version of it. classes did more damage and healing, had better regen, threat reduction was overall worse but as long as casters stayed out of melee range threat wasn't a big deal because tanks had more consistent rage generation to keep threat up (overall, the difference in tank threat and non-tank threat was larger than it had been but it was a gradual change throughout the patches)
this was the "all right we got everything in vanilla the way we want it. we can now work on BC"