I don't think anyone needs to get it done. But Blizzard has been doing this massively-overtuned-at-release-nerfed-later thing for a while and that seems to be their point.
Guilds getting to Gul'dan now won't skip much because their dps is likely to be considerably worse than yours. I don't think the fight being trivial for people who've already been killing it for weeks is the end of the world.Well fortunately it is that trivial.