they hold the record. And the server they did it on was harder than Classic is now. By proxy, they did naxx, at a world record pace, while the content is dramatically overtuned. They are the best guild as of time of typing.
You’re suffering from Dunning Kruger.
How many bosses on the LH core did you kill? What’s your classic progression? What’s the basis for your beliefs? Why are you smack talking the best tank in classic on a retail alt?