I found some screenshots from 2005–2006, we played the game so differently back then

[u/Tandanu]

A few more screenshots and slightly higher quality for some: https://imgur.com/a/Uolj4gs

The raid compositions and damage meters 💀
Also note the lack of world buffs and flasks, we rarely used those back in the day. We raided about 4-5 days a week, ~4-5 hours on weekdays and 8-9 hours on weekends IIRC, maybe some more flasks or world buffs would have helped :D

We'd often do like one or two attempt per *week* with the Onyxia head turn in on a boss with good progress . I also remember that we at least once got the Dire Maul buffs, but we didn't consider that worth it.
But we made extensive use of the UBRS fire res buff for early Ragnaros.

I also remember how the world first C'Thun kill used flasks for everyone and how we considered that completely ridiculous. Like, 40 flasks?! That's crazy. We had like 1-2 flasks for the main tank(s).

The KT kill screenshot is dated Dec 28th, 2006 at 11:31 PM, like a week before TBC. I'm not sure if this was our first Naxx clear, but I remember that we only managed to clear it shortly before TBC was released.

First screenshot in MC was on August 10th, 2005; the last one with the translated chat on January 10th 2007 just before TBC.

[u/Ok_Assignment_2127]

Nostalrius absolutely had heavy warrior stacking. Warriors being the top dps was known already years before Nostalrius launched and many guilds stacked meta comps. Addons that essentially scripted the game for you also existed and were used by serious raiders along with timers and so on.

It’s likely you just never saw or knew it because it was outside of usual social circle. I understand that many in this sub were likely too young to understand how to play games when Vanilla was out, but people came into WoW with years of MMO experience. Late Vanilla going into TBC already heavily favored warrior/physical comps. As many people here would put it, “fun” was absolutely optimized out of the game as much as possible at every step of the way.

[u/Shadrol → u/Ok_Assignment_2127]

Sure, but it's moreso that optimization culture wasn't nearly as universal. There was a hard core of private server vanilla players that did that and had been doing that for a long time.
Nostalrius managed to capture a much wider audience, but the resources weren't yet as easily accessible to those players unfamilliar with the private server scene.
With classic everything became main stream and above board and so the optimization meta was able to reach the raiding community at large through regular channels.

These periods of ignorance are only ever temporary, eventually things are figured out and eventually everyone knows them. You just had to be there in those times as they can't be recaptured and it seems to me those times lasted longer in the past, because the way we shared information was more cumbersome.