If you use Duty Finder. Don't expect everyone to wait for you to watch cutscenes.
If you use Duty Finder. Don't expect for everyone to engage in a speedy run.

Its a double edged sword. To put it simply, use Party Finder to make a group for the type of run you wish to do.

For the Main Scenario Duties, this is how I see it. As long as one healer and one tank aren't watching the cutscenes.. just roll with it. Complete the instance as normal. You only need ONE tank, and ONE healer and any amount of DPS or No DPS to complete it. Let the people who want to watch, sit and watch. They're just missing trash mobs anyway.

If you can't continue without the peeps watching the cutscenes, then learn to play. Seriously, Praetorium and Castrum Meridium are one tank one healer fights. The only time you need mostly everyone present is Ultima Weapon, second phase, last 10%. All cutscenes will be done by then.

This is a player issue and one we can fix ourselves. SE doesn't need to be involved.