It's common for story content to have new players in and it's common for them to make it a bit slower than it would be if, say, everyone was a veteran that knew all the little ways to speed it up. It's not being rude it's just obviously true.

What may speed it up is using sprint, tanks grouping up enemies together, doing aoe rotations (which attacks multiple enemies instead of one at a time), having the best gear (for that content it's ironworks item level 130 gear) and item level 510 food. These things are probably not understood by a lot of new players.

It takes a healer about 7 seconds to resurrect someone which can be difficult when there are mechanics to do, but they can instant cast one of them every minute. It's common for a healer to only resurrect one person every 60 seconds, but there are two healers so you may often only see two resurrects every 60 seconds. If it's not necessary to resurrect more than that they might not bother, especially in level 50 content where things die quicker.

You should never return to the beginning unless everyone is dead and the boss has reset, or at least make sure that all healers, summoners and red mages are dead and that none of them got offered a res.