I feel like people are talking about two different types of people here. There are the people that want to go in blind and learn as they go for their first time, which is great. It's fun to figure things out on your own, and a totally reasonable thing to do this close to patch day.
But when you don't know anything about the fight and go into it expecting everyone else to explain it to you right off the bat; well in that case you probably should have looked up the fight first / read a guide / watched a video. Not only is it a massive waste of time which could be spent learning/clearing the new fights, but it can ruin it for the other people who want to run it first without being told what to expect.
EDIT: I want to believe that the 'watch a video' comment was directed more towards the second type of person rather than the first. At least I hope it was lol.