My guild killed untauntable BWL drakes in July 2005 and almost killed a HORRIBLY bugged Chrommaggus but he leashed back away from the raid before we could. We also got pre-nerf Ouro down to 9% before he and C'thun got nerfed. Gear mattered at that time, so that's my frame of reference. It mattered far less months later when everyone knew the strats and mechanics.
Also, old raids were nerfed when new ones came out. Molten core was nerfed, and so was BWL. I don't remember what mob it was, but I do remember one of our healers noting it was far easier to heal people in MC runs after they patched in BWL (or right before it opened, it's been a while so I don't remember the exact time). The mob I'm referring to went from hitting tanks for 4K to like 2.5K. I'm less certain if AQ was nerfed other than the big nerf to make C'thun and Ouro killable. Naxx never was because it was the last raid of vanilla.
That's all just history e-peen tho
Assuming they release everything with patch 1.12 values, it's true that content up to Naxx will likely be piss easy.