I’m thinking from a rotation perspective.
When I play a class I don’t always want to manage resources or anything like that.
A simple rotation or set of skills is sometimes a bit more chilled.
So which class is the easiest melee to play? Top 3 maybe?
Have not tried all melee personally, but I think the general consensus would be Demon Hunter as the most simple spec.
Stupidly OP as of the prepatch, so probably not a bad time to level one if you want to play it in DF.
If you’re going for the trifecta of threads or a quad combo I’ll pre-empt you and say resto shaman and bm hunter for healer and ranged!
Recently levelled one to 50 
Played all classes to lvl 60. My favorit melee are
1 arms warrior
2 Blood dk.
I also enjoyed kitty druid but not sure how it plays with the new talents
While DH is prob easiest, Fury warrior just hit buttons when they light up 
Fury warrior
Warrior, always has been, always will be, and not just in terms of melee. However, you must first make sure that you have a keyboard able to withstand the intense facerolling.
Several iterations of Warrior have been among the most complex specs in game. If you were to look at WOTLK classic, Assassination Rogue is both the easiest to play melee and the highest dps. If you were to look at melee in TBC the easiest was Combat Rogue or Enhancement Shaman, with the hardest either being Arms Warrior or Feral Druid.
And right now in Dragonflight, classes are overwhelmingly easy, pruned and dumbed down as a whole. But melee has always been harder than ranged, because they have to dodge more land mines.
You and I already had a similar discussion to this one on my classic char some time ago, but I will give you a reminder:
Yes that’s a fun meme and Bladestorm is a fun ability. Being able to press a cooldown once every 2minutes to do high damage is not the entire spec. In terms of gameplay complexity in Classic, Warriors are not among the easiest. Several iterations of Arms in particular were changed because the gulf between the average player and the high end player was too large, twice it has had mid expansion re-designs, the last being during Legion.
You having a crying fit because a Warrior killed you with Bladestorm in Classic is not remotely any measure on how hard a spec is or isn’t to play well in the game, especially not in Dragonflight, 15 years later. Especially since Bladestorm isn’t even used on single target other than as a rage filler where you cancel cast it, assuming you’d even pick it (nobody does, currently).
Crying because I answered the question of the OP? Seems to me like you were the one here who took offense. Rage bar full?
As someone who played original WotLK on fairly high rating, I can say that video exists for a reason, and memes are usually not as funny if there isn’t some shred of truth to them.
Either way, not bothering with this again=)
You’re definitely crying when the OP is asking about Dragonflight and you’re still crying about that one Warrior that Bladestormed you to death in Arena in 2010 and now you’re basing your whole opinion on an entire class on your trauma from getting globalled by a Bladestorm you walked into wide open.
It’s time to let it go, no Shadowmourne Warriors are going to Bladestorm you on Dragonflight.
Demon hunter
Frost dk
Havoc dh and fury warrior are the most simple and repetative but I also find the most boring to play.
Fury warrior every time /endofdiscussion
The first thing that comes to mind is Fury warrior, That’s gotta be the easiest.
Lots of Fury Warrior shouts!
I guess no classes are really super hard any more, but is Fury really any more easy than Ret for example?
Where does Unholy DK come into the conversation?
Of the melee specs I’ve played (most, but not all), I think ret paladin is the one I find easiest to play. You don’t need to make rotational decisions all the time (beyond using AOE spenders in AOE and ST spenders in ST), and you don’t have to target swap.
Havoc used to be the easiest, but the new tree has added some complexity (depending on which talents you take).
Feral is probably in the more complex end of the range, although not as complex as something like outlaw rogue.
Depends on content generally for pve id go dh or fury warriors