There are two problems I have that can affect what we are seeing.
One, having a melee weapon to parry with in melee has no effect whatsoever on your defense. I suppose this is why something like making a ranged attack while in melee range provoked an OA in the past (It did, didn't it?) because if you were shooting you weren't parrying.
Two, shields just aren't as useful as they seem to have been historically, especially against ranged attacks. Defending against a ranged attack with a shield was easy, just put the shield in front of you.
I'm not certain how one could mechanically simulate either of the two things I've described. Maybe say that any ranged attack or casting a spell with a range provoked an OA from opponents in melee range. And for point two you could say that a shield is +4 or whatever vs. a ranged attack instead of +2.
I don't know....I think shields are a pretty big deal. Anything that raises your AC by 2 at almost all times is a solid option. However, it comes at the cost of some damage potential because it limits you to one handed weapons. So it is a trade off....and one that would seem to always be classified as a negative in this discussion because the end point seems to always boil down to DPR and only DPR.
There is the Shield Master feat, which is pretty cool. It allows you to use a bonus action to shove a creature when you attack, which either knocks them back 5 feet or knocks them prone. That's a pretty solid option since all your attacks after that would have advantage on that target as long as the shove worked. Then it also allows you to add your shield's AC bonus to Dex saves. And it also allows you to use your reaction to take no damage on a successful Dex save when you would otherwise take half damage (like a fireball or lightning bolt).
The sad thing is that such a feat may be a great option for a melee combatant. But because we can't easily calculate the increase in the amount of damage that it may lead to, it won't even be considered in these discussions.
But even so, opportunity attacks are still being overvalued here.
I don't think they are at all. I don't think that you're realizing or at least acknowledging how they actually affect play. [MENTION=1560]Corwin[/MENTION] summarizes it pretty well. Keeping enemies at bay and helping dictate who they focus their attacks on is a huge factor.
And yes, the melee warrior still will carry a ranged weapon, but he is far more penalized for fighting at range than the ranged warrior is for fighting in melee.
I agree with you there, if specific feats are taken by the archer. I would expect that the melee fighter would have other feats that will boost his performance in another aspect of play. DPR isn't everything. But yes, archers are not as limited in melee as melee is limited at range, assuming certain feats, in a comparison of DPR.
However, let's say that the melee fighter has taken the Heavy Armor Master and Tough feats. So he's taking 3 points less damage per hit than the archer is taking (assuming non-magic weapons), and has more HP to spare. He is more capable of taking damage than the ranged specialist, and therefore, at less risk while in melee. Comparing the amount of damage each can take instead of how much they can dish out paints a different picture. Especially if the melee fighter also uses a shield and has selected his other abilities to compliment these choices.
Damage output is a big factor. I would never deny that. But it's hard to really examine things when it's the only metric used to gauge the already subjective "effectiveness" of a character.
They exist in all instances where the archer doesn't have Crossbow Expert. Are you just pretending that archers without this specific feat don't exist? All archers start as level 6 fighters now, having used their two ABI's for Sharpshooter and Crossbow Expert?
I agree that ranged weapon combat is a little too good compared to melee combat, but I feel you are overstating the case just a bit.
Variant humans, I bet. Allows this effective build to take place much sooner in the game than it likely should. The earlier in the game an archer has both of these feats, the more imbalanced it will seem compared to other approaches to combat.
Crossbow Expert is not necessary. You can just draw a rapier with your object interaction and attack with that.
True but then the person is either limited to a hand crossbow for less damage, or to one round of OAs if they wield a heavy crossbow or bow. Right? Wouldn't he have to use his item interaction to stow the sword next round? So basically, it seems like every other round he'd be able to have it out and ready for an OA.
I think DM judgment would likely play a big part in this.