I can understand watching the dialogue on the way to level 50, even through some of the level 50 instances. However, the one thing I hate is when we are in an instance that a level 50 can easily solo and people insist on watching the dialogue. If you REALLY want to watch the dialogue in places like Esseless, Black Talon, Maelstrom, Foundry, etc. then go solo the place on normal and RP your heart out.
Irrelevant, and a straw man at best. Just because it can be done solo at 50 doesn't mean people should feel compelled to skip dialog. The cutscenes are meant to be watched, with the option to skip. I get that some people like to blow through everything. But if someone doesn't want to skip, they are 100% entitled to watch every second of every cutscene. The same holds true regardless if someone has run the instance once or one hundred times. The bottom line is that non-skippers are 100% in the right and should not be dictated to or pressured into skipping.
Don't like it? Politely ask the group if everyone would spacebar. If not, deal with it or join another group.