4Ed have try to level the experience of all classes. It has been a dramatic failure.
It was a commercial failure, for a veritable perfect storm of reasons, including the nerdrage that surrounded it making it less likely new players would even try it.
But concluding that balanced games are bad, and, conversely, broken games are good, is not valid . Not just because it's
ad populum reasoning, though that's enough, by itself.
So the solution is in the role play.
Nope. Never. (Yeah, that wont' get me in trouble; at least I didn't say "Stormwind Fallacy" ...oops. ) If you have to work around the system to get the desired RP results, it's just proof of either a bad system (as has consistently been the case with D&D - I'm sorry, I love the game, but I love in
in spite of it's many, deep, and abiding flaws) or a system with design goals incompatible with the desired RP results.
Fighter and wizard are not competing to win the game at the end of the session
The player who play a fighter is there to feel and make live a fighter hero in a world of magic..
Two very strong points that argue to exactly the opposite of the conclusion it sounds like you might be aiming for.
A
hero in a world of magic, is one who makes a difference in spite of the many challenges posed by that magic. Not one who's just a pawn in a game of wizards, whose decisions and actions make no difference, who's readily replaceable with a golem or summoned monster or off-the shelf mercenary.
The point of a cooperative game is, similarly, for everyone to contribute to winning the game. You don't win that game by making choices to keep another player down for your own glory. Making good choices needs to stand out as a good contribution - even if, say, they're sacrifices. An option in a cooperative game that requires the player to make decisions that net harm the overall chances of winning, in order to appear to be making an important contribution, is a trap option....
Not necessarily in the sense that nobody has ever honestly argued it, because this is the internet and I'm sure somebody has, but in the sense that it's the weakest and most ridiculous version of an argument that can hold some water.
TBF, it was a smaller part of the defending side of the Fighter SUX arguments on Gleemax… and I was too often forced to use it, myself. So there's some bitterness in there. ;(
Without going into too much detail, the broad-strokes panorama of the sorta-consensus we came up with back then, on keeping casters & non-casters, in general, and the LFQW with the elegant-design, but Tier 5 fighter as the L (also, honorable mention to the much less inferior Tier 2 Sorcerer), and CoDzilla and God-Wizards as the Q, often abbreviated as "Living World" was for the DM to devote the campaign to making spell prep & cast choices /exceedingly difficult/ via profound time-pressure, uncertainty via downright telegraphing some threats and presenting equally trustworthy seeming disinformation, and a constantly-changing tapestry of challenges. The idea was to balance the Fighter by either/both making the 'day' drag on so long that the casters were tapped out of their best combat spells for multiple combats, relying on the fighters through some important battles, or, were so uncertain and so fearful of needing spells later that they passed on casting them even at ideal moments, letting the fighters shine (but not the party die), then being left holding spells they ended up not needing later afterall. Similarly, BTW, wizards could be goaded into taking slates of highly situational spells that turned out to be useless due to disinformation, allowing the sorcerer a chance to shine spamming some generally-useful spell that was OK in the situation, while the wizard cursed himself for not prepping the /ideal/ spell. ...at the extreme fringe of that, there's "but what if the DM isn't doing a good enough job forcing the time pressure" and "well, your
fighter as the 'natural party leader' should talk the party into showing some heroic fortitude and bravely pressing on!" Which, actually, sounds kind good - especially after selling the Living World concept all through a long thread - but, which, really, when considered for the perspective of designing for a
cooperative game is quite dysfunctional.
It's not so much the matter of the DM applying just the right pressure every day as it is them applying different amounts and diverse varieties of pressure from day to day.
That /is/ the right pressure, yes. I should've made it clearer that it wasn't as simple as always applying exactly the /same/ pressure.
As long as the party doesn't know whether they're going to be facing one encounter tomorrow or ten,
Yeah, see, you get it.
then keeping around a fighter or other long-day character is a good investment.
That's the idea, the problem is that it rests on grinding down the resource-heavy characters, and reducing the overall effectiveness of the party, in order to glorify the low-contributing character.
The bottom line is that kind of balance-by-pacing mechanism both restricts the kinds of stories the game can produce, from the narrative side, and is dysfunctional as a cooperative game, on the system side.
If it weren't so enshrined by decades of tradition, the hobby would regard it like modern doctors revisiting the possibility of using leeches*.
* example chosen advisedly, because, yeah, actually, there are a few legitimate medical uses for leeches!