I play to 95% evil chars, and I have NEVER died with ANY char in a 1vs1 against a monk. EVER. I have however, killed a bunch of Maran/Acolyte/Trib/Herald monks with: AP, Warrior and shifters. (Never played invoker and my drow Outlander trannie attempt was a big failure.)
Invokers can, in the right hands, be insane! But, if you're not used to or good with invokers they're... Well, hard to land kills with.
I'd say that 90% of the invokers I never fear unless they have a gang to support them with lag and/or summons. The other 10% however... Holy hell they scare the shit out of me! Either because they're so good with hunting or that they always have earthbind on the go.
Lvl 20 earthbind rod = works against all classes that makes use of potions/scrolls to fly. However, I agree, against a Maran or a class that can cast/commune flight, it's useless. But most potions/scrolls of flight are lvl 5-25. (VERY few are lvl 40+)
So... All in all I say:
SOME invokers are broken.
NO monks are broken.
Coming from a guy that's spent a lot of time fighting both classes but NEVER played either. ;)