Two-handed weapons in Diablo 3 are mostly worthless as they exist in the game, pre-Reaper of Souls at level 60. Unless they’re a pre-patch, pre-2.0 Skorn, chances are they aren’t going to do much damage in contrast to one-handers.
According to Blizzard, this isn’t a bug, and community manager Nevalistis took the time to explain why these weapons just aren’t performing as well as one might expect:

This, and the OP's post, is a good analysis of what's going on here. Allow me to expand on this and offer insight from our perspective.
When we set out to redesign loot in Diablo III, we knew these changes would need to take the expansion into account. This means that it was necessary to create these changes in the scope of the 1-70 experience. The unfortunate byproduct of these changes is what's laid out above – iLvl 63 became level 63 items, which in the current pre-expansion and level 60 experience means they no longer drop.
That said, this issue is unique to the transition time between patch 2.0.1 and Reaper of Souls. No one should experience this when playing the expansion – it's completely unique to the current environment. We understand it's created some awkward moments while playing (i.e. "YAY, a Legendary! Ohhh… it's a 2-hander…"). In order to get a completely full picture of this situation, we can re-evaluate both where potential changes may need to be made and what the best, most informed way is to make them after we can observe the 1-70 experience in a live environment.
For those not in the know, level 60 two-handers previously contained iLvl 63 stats. As they are right now, they roll stats at a level below 60, and that is why they suck. I don’t expect this to be fixed at any time soon, as the game is now balanced for Level 70.
The change is more likely the result of poor planning rather than a deliberate ploy to get players to pick up Reaper of Souls.
