Scaling issue?
I did map completion there yesterday, and I didn’t notice any problems. Make sure you’re not in an area that’s too high for your character. Also, make sure you’re not just standing there in the middle of a group of mobs, soaking up damage. Dodge, use blocks/invuls, and heal yourself.
If you’re at level 80 with cheap quality blue/green armor, when you’re downscaled you’ll find that many of the mobs have better stats than you. Perhaps this is what you’re discovering?
Lorgus brings up a good point. I mean, you can still easily survive in blues/greens, but they need to be within 10 levels of your character level. So, if you’re on a level 80 with level 65 greens/blues, no trinkets, and no traits . . . yeah, you’ll probably die a lot.