The narrative of C'Thun is a story of pity. Players threw themselves against the boss for weeks to no avail. He took a great deal of wow classic gold damage to take down before he enraged and promptly murdered everyone, and the struggle demanded pinpoint positioning out of all the raiders. The battle famously had a bug too, which caused ranged tentacles to spawn behind walls or directly under gamers, almost guaranteeing full party wipes. After 80 days without a single clear Blizzard eventually nerfed C'Thun into the ground, and he was easily beaten the same day.
It's not merely the raid as a whole is easier for today's seasoned WoW gamers.
"As for pre-nerf C'Thun, there's absolutely no doubt in anybody's mind that contrary to the meme that came from 2006 IRC logs, pre-nerf C'Thun is absolutely not mathematically impossible. Players do triple or even quadruple the quantities of people's DPS back then so even a pre-nerf C'Thun would readily collapse. It is a matter of the playerbase being more skillful, and educated.
If you take a close look at the damage logs of any C'Thun kill right now you can see that's true. You've got players doing between 200 to 300 dps on managers, and because this can be Classic WoW you understand they're watching a movie in their second monitor while they do it. It's tough to find precise numbers, since most people were not keeping track of dps 15 decades back, but based on Minmaxed, it was much less than what we are seeing now:"[There's] a general consensus among people who did perform back then is that it was'way less.' The idea that pre-nerf C'Thun is too high a damage check is laughable."
Practised on our own client for several weeks until it went live, developing strategies and getting familiar with the litter and experiences," Minmaxed explained. "I think most of the guild could have liked C'Thun to be harder, but when talking about the entire mathematically impossible' C'Thun I do not necessarily think it was as much about maths because it was about the encounter being calmed with tentacles spawning inside of cheap wow gold classic walls and beaming your raid while being out of the line of sight."