Someone at Blizzard keeps listening to the vocal minority that want everything to be punishingly hard. And lets face it, there will always be a subset of those people that will say WoW is too easy no matter how difficult the devs make things. That subset of individuals should NOT be driving design.
For an anniversary event, for something where nostalgia was supposed to be king, it really should have been tuned to be easier than the current raid, should have been a place for people to get easy gear upgrades even if not optimal ones (sorry for everyone that loves mastery, lol). Guilds should be able to clear it quickly before going back to their normal raid progression without worry of making sure they have the correct number of players and it should have just been “fun”.