They have said that they arent making any major changes to the classes or specs. If that holds true, we will see.
But here is a history on Frost Dk that im sure Dreadmoore is going to call me a liar on, but you can go check it for yourself.
Frost
Nerves of Cold Steel - Increases Off-hand Damage by 25% (with full talent upgrade) added in 3.0.2
Threat of Thassarian - When dual-wielding, your Death Strikes, Obliterates, Plague Strikes, Rune Strikes, Blood Strikes and Frost Strikes have a 100% chance to also deal damage with your offhand weapon. Added 3.2.2
Might of the Frozen Wastes was added in 4.0.1 and Increased all melee damage by 4/8/12%
Patch 5.0.4 Might of the Frozen Wastes now also causes Obliterate to deal 40% more damage when wielding a two-handed weapon. No longer gives autoattacks a chance to generate runic power.
Threat of Thassarian 5.0.4 No longer affects Rune Strike of Blood Strike and causes Frost Strike to deal an additional 50% damage when dual wielding.
Then the damage increases to certain abilities from ToT were baked into Might of the Frozen Wastes in 6.0.2 and then it was removed in Legion.
ToT still just allows both weapons to hit the target when using strike abilities like Obliterate.
Before Cata there wasnt this focus on certain damage with weapon types and Might of the Frozen Wastes was introduced for 2h to try to offset the increased amount of KM procs as well as Razorice that DW had. Even the guides from back in Wrath would say that 2h was behind because of these.
Dreadmoore will make the argument that this isnt true in wrath, but then why add more weapon damage to 2h if it was already beating DW and not touch DW?
The tooltip for ToT I had to get from a Wrath Talent Calculator since the Gamepedia one is stuck back from MoP.
You also hear the argument now that weapon strikes dont do enough damage, which isnt a weapon issue. The strikes are calculated by attack power, no weapon damage involved. I calculated the damage of Obliterate for Trumpknight before armor. I came up with 10,297 damage and in another thread they said that their Obliterate damage was 10,432 damage. Then you add in enemy armor and you see a lower number.
So it is not a weapon issue at all for damage. Its a spec issue and has been all expansion long.
If people want 2h, ask for transmog. That is the best way to get it back.