I mean yes, you should have a proper pride route...

When not doing low keys the DPS needs to prepare: which packs/targets are prio, where do I need to interrupt, how do I avoid taking excessive damage

Healers needs to know when a lot ab pulls and cds and as does the tank.

The tank also needs to know routing

These are just things that has to be there for playing keys. If you're not prepared for a dungeon, you shouldn't queue for it.

Not having a perfect pride route is ok for a lot of mid tier keys as you'll most likely time it anyways, but it's a time waste to not plan a pride route which is counter productive when you're literally on a timer. People shouldn't flame when you're just playing a game, but people should also be prepared for the content they sign up for.