This is not inherently true. Try telling those who practice fencing, Laijustsu, Kendo etc that fighting is just simply chucking metal around.
Gamer designers *can* make martial combat more than a simple activity (and still keep the physics bending nature of wizards intact) but I am not totally sure DDN has got the balance right.
The issue isn't how realistically complex fighting with a sword is, but how many interesting decisions the player gets to make each round. 4e gave fighter players
many decisions. There were a lot of decisions even before you chose your at-wills or decided on which encounter or daily power you're using turn.
I'll give an example. Last session, 4e (conversion of Way of the Wicked, a Pathfinder adventure) the PCs went up against a good elite wizard and his three town guards. (The PCs are evil in this one.) Naturally the wizard, an evoker-type, stood behind the guards. The relevant PCs were a cleric, eladrin rogue, and a fighter. The party had fought this evoker before ...
and lost! Both were familiar with the other side's abilities.
Right at the start, the cleric hit the wizard with Bane, which inflicted -4 to hit and defenses for 1 turn. The wizard decided not to use his action point, nor his recharge when bloodied power in the first round because he'd be wasting them. That gave the fighter enough time to get in the wizard's face and attacked. He took an opportunity attack from two guards (getting hit once) to get there and was marked by the guards. Therefore simply attacking the wizard would provoke Interceding Strike (a slightly weaker version of Combat Challenge) along with -2 to hit. The fighter decided it was worth it, hitting and marking the wizard, and taking an incoming Interceding Strike.
Doing all that required the fighter to make three decisions: who to target (dangerous evoker or guards), to risk getting opportunity attacks, and to risk attacking the wizard despite being marked, with a bonus counterattack on top of it. In exchange, he hit the wizard, marked him, and was right beside the wizard which made casting difficult. (They knew the wizard had no close burst/blast spells.)
The next round the rest of the PCs were nuking the guards, and the cleric's turn ended without much effect (I think he missed with Sacred Flame). Two guards were bloodied, and the other advanced on an engaged a squishy PC in combat (and was also bloodied). The guards had to decide whether they should defend the wizard or advance. Two decided one way, one decided the other. The guards near the wizard knocked the fighter prone.
The wizard's turn came up. He was marked, next to a (prone) fighter who could probably smack him if he shifted. The fighter had lots of armor but also a shield. He could drop a Fireball on the fighter, but the cluster of PCs across the way was such a juicy target. One guard was in the potential Fireball pattern.
The wizard (meaning me, the DM) decided. The wizard shifted, and came
this close to getting hit for daring to shift away from the fighter. Fortunately had he been hit he could still finish the shift. (Or so he thought. It turned out the fighter could have dazed him, ending his turn!) Then the wizard nuked. It was a thing of glory. Three of five PCs were hit by the Fireball, and the guard was missed (but took half damage and died anyway). Maybe the wizard should change his alignment to neutral
And then the wizard used his minor action (he's an elite) to hit the evil cleric. The evil cleric and another PC were bloodied, but the eladrin rogue in the middle wasn't. The wizard spend an AP to use Scorching Burst, and he had to decide whether to "burninate" the evil cleric or another bloodied PC, both patterns would include the rogue. The wizard scorched the cleric and rogue, dropping the cleric.
The cleric is an uber-healer, but the players decided they were too reliant on him. Many PCs had since the last battle multiclassed with a leader class, and someone revived him. All that work gone to naught.
The fighter got in the wizard's face again, and pondered using a special power that would simultaneously grab and damage the wizard, and then the eladrin rogue teleported into the perfect flanking position and did nasty things to the wizard's guts. Dead wizard.
Look at the number of tactical decisions the PCs and wizard (and guards) had to make. Many (such as blast patterns) are identical across edition (not in terms of details such as blast size, but you know what I mean).
On the other hand, the fighter had numerous tactical options that his 5e equivalent wouldn't have had. He had to risk ignoring the guards (and paid for it), not only getting incoming OAs that marked him, but getting set up for a punishment strike (which in fact hit him).
He got in the wizard's face and marked him. At minimum, the wizard was taking -2 to hit everyone but the fighter, a big deal for an AoE using wizard. (The 5e fighter can only apply disadvantage to one attack.) The fighter could punish a shift, and only a really bad die roll prevented him from doing so. How do you punish that kind of movement in 5e? (Don't say readied action, that's an option in 4e too, and the 4e fighter could ready an action
and punish a shift.)
A 4e fighter isn't just hitting things for high damage, with maybe an OA or high-damage strike for seasoning.
Also note that the fighter's actual weapon (a flail) wasn't really that relevant. I have little interest in "realistic" combat because D&D is not realistic, even the non-magical part, and I find realistic rules to be a negative.