Originally Posted by
Netherling
That's complete bullshit. Guilds that had done (enough) AQ40 and BWL definitely did progress in Naxx40, as did guilds, that completed BT, progress in swp.
As many people have said, it's very hard to compare vanilla / tbc difficulty to modern difficulty. Modern bosses are harder - mechanically and numbers-wise. However, pretty much everything about vanilla and tbc was harder. These days every class has a few 'oh shit' buttons, speed boosts and better class mechanics to cope with the harder difficulty of bosses. In the early days many specs weren't fully viable (especially in Vanilla), classes and specs were very clunky and gear was unpredictable (spirit plate etc.). There were still good players, they were just rarer and the difference between a good player and a bad one was huge back then.
So judging actual difficulty is very... difficult because of the skills available, the state of the game and servers, classes and their availability (remember in vanilla horde had shaman and alliance had paladins) and addons. It was hard back then and it's hard now but for different reasons, in my opinion.