Runs like these will happen from time to time. It sucks, but those Main Scenario dungeons are easy enough that a few people can clear it just fine while half the group watches cutscenes. I had a run in praetorium once where 5 people were new and wanted to watch the cutscenes. Me (MCH), the tank, and the healer basically blew through the place and downed a few of the bosses ourselves. No one was butthurt about it and it was actually a lot of fun because it provided just a sliver of challenge to those old instances. Don't let it get to you. Like you said, the majority of this community is incredibly friendly. But the bad apples tend to stand out like a sore thumb. Just don't let those bad times affect the way you enjoy the game. Happy adventuring! And welcome to Eorzea!