Not to be rude, but inexperienced or willfully obtuse players isn’t a defense. I’ve had characters play very unoptimized or underpowered characters and enjoy it, usually right up until an actual optimized player blows them out of the water in a similar field. Once again though, and I’m sure people are tired of hearing it, this is a defense of the idea of balance, that 5e gets it “close enough” that players don’t feel obligated to min-max out of necessity.
Or skilled players that have a different play style, perhaps?
Explain to me how an "actual optimized player" blows them out of the water? How your optimized character prevents me from playing the character of my choice, and doing so well. How does your optimized character limit anything that I can do?
Because that's difficult to do when the purpose of the game for them is to role-play a character, with the strengths and weaknesses, as a "real" person in a "real" world. That's not necessarily the purpose for everyone, but it is a valid and popular play style. Just as much as a group that prefers min/maxing.
The game isn't designed like MtG or a board game, or other types of games where it's a competition against the other players, and you're looking for the combination(s) that give you the advantage, and that there is one "best" combination for a given class. It can certainly support that style of play, but it's not the default design or the default method of play.
3e/3.5e and 4e were certainly better suited to that approach than other editions, and 4e seemed, in part, designed around that specific concept of balance.
More choices does not equal more balanced. More choices is more difficult to balance, because there are more things to try to balance. It
can be balanced, but simply adding a choice doesn't guarantee it.
So the problem I think we're running into is one of definition, and the fact that we're jumping back and forth between two different kinds of balance/optimization.
There's the balance/optimization within a race or class, and then there is that of the game itself. Within a given race, they are generally optimized toward a particular class. In which case you might consider that unbalanced. But within the game, it's balanced against the other potential race/class combinations.
The half-orc (like all of the races) are unbalanced within themselves. Perhaps the half-orc moreso (I don't personally think so, but that's partially dependent on what somebody is looking for, so others obviously disagree). That is, the half-orc is optimized for being a Strength-based barbarian or fighter, which means it is unoptimized in being a bard, wizard, or rogue, for example. This is what I mean when saying optimized equals unbalanced. Unbalanced does not equal unplayable.
However, within the context of the game, the half-orc
is balanced in regards to other races. It's strengths and weaknesses are different from the other races, but all of them can be used interchangeably within the context of the game. You can play a half-orc of any class, or even an entire party of half-orcs of mixed classes (optimized or not) and successfully play any of the published APs. Statistically, they won't be any more or less likely to complete the AP without dying, although the players might use different tactics to succeed.
In the past, many published adventures required certain classes (I don't recall any that were race-dependent), or magic items that provided the functionality of missing classes. In 1e the biggest requirement was some form of magical healing. You could go without it, if you were using the original mega-dungeon concept of Gary's home campaign where you'd go as far as you think you could, and still return without dying to rest for a week or two to regain all of your hit points. It was much, much harder to do that (if not impossible in some adventures) to go without magical healing and play a dungeon from start to finish without returning home to heal.
Of course, the cleric was the easiest way to guarantee you would have access to magical healing. At which point the expedition and return approach was no longer required. The published adventures, with some exceptions such as
B2 Keep on the Borderlands assumed that you had some way of healing, so you would not have to return home, although they generally always contained potions of healing, etc. In theory you could rest for a week within a dungeon, but it would be very difficult.
The design of 5e is quite different. It is designed to be played with any mix of races or classes, and balanced (perhaps the term optimized would also apply) for a party of 4 of the same or similar levels. It doesn't presume the use of magical healing, magic items, or even spellcasting. Although more classes than ever (and even some races) have spellcasting.
The races (and classes, as always) are designed to fill different niches. Those niches are both mechanical and story/setting based. Half-orcs fill a particular niche. But if you want to swap out some abilities (such as giving them a bonus to Intelligence), it will not break the game. The game is balanced in a way that you can swap things around if you'd like, although there will undoubtedly be some things that might break the game.
Give a half-orc +2 to Charisma instead of strength and they'll make a great sorcerer or even bard. Or a +2 to Intelligence, and make a wizard that also has an edge on melee combat. Personally I don't think changing the ability bonus is necessary - because all of the classes will work just fine without changing it. But if it's that much of a big deal, then change it.
I understand the arguments that a 15 Dexterity is "better" than a 15 Strength. Mathematically, due to the specific benefits you gain from Dexterity, it gives you some advantages. But it doesn't guarantee a "better" character. A group that prioritizes role-playing above optimization has no issue with that. First, because it's not a game of comparing your ability against the guy next to you. Second, because the focus is on overcoming the challenges in the course of adventuring. You will have your strengths and weaknesses, and you're goal is to find ways to do that. Just like the wizard tends to hang back and out of melee combat because they know they aren't good at it, a Strength-based fighter might make different decisions than a Dexterity-based fighter. A half-orc sorcerer might do things a little differently than a human sorcerer. It has nothing to do with inexperience nor being willfully obtuse.