I do not do HM's over and oaver for story. It gets to be like watching the same commercial repeatedly. So yes, I will still ask folks to skip. That said, if someone is new I have no issues. Can sort of guage this by gear and play skill.
It's not just "your" time but the three others in the group. Do story mode, bring friends that want to see it as well so you have 2/4 or 3/4 of the group.
Expecting folks to watch the story for the 100th time is just as bad as being a "please space" person.