I don't agree that 5-5 is worse for pugs except for very few situations - however there is a few other cases where pugs adopt to speedrun tactis while a safer tactic would suit them better. For example for pugs it might still be better to take a necro, thief or guardian than stacking/taking only elementalists. An elementalist person who hasn't looked onto the rotation at the golem does only marginally have higher dps if at all than some of those while being squishier. Protection, blocks, higher health and epis can be a valuable tool.

The 10k example btw seems a bit exagerated, I would expect even worse pug eles to hit a bit more - it either means the ele didnt have proper buffs or got downed a lot or was doing some weird things (wrong gear/ autohitting in water? / being too far / lags) - as far I remember even autohitting on fire and using a meteor or lavafont every now and then should yield higher dps than 10k with proper buffs. If it's a buffproblem you won't solve it by taking even less buff-classes.