It's an easy enough statement to agree with on the surface, but it goes a bit deeper than that.
Suppose you worked at a job where you were discriminated against, but for various reasons, you stuck at it. Then, the company restructured and instituted new practices that treated all the employees fairly. You would be happy
simply because you are now treated fairly.
That said, balance remains important. It is my view that they who can give up essential balance to obtain a little temporary fun, deserve neither balance nor fun.
There's fair discrimination and unfair discrimination. It would be fair to reward people who worked harder at their jobs, and even those who have certain natural aptitudes that make them better performers at their jobs.
What's unfair is rewarding people in an opaque and haphazard fashion, right?
Going back to D&D, it's not unfair to say, roll ability scores randomly, since the process is entirely transparent and everyone has an equal shot at the high and low scores.
What is unfair is putting "trap" classes into the game, that look good on the surface and ought to be good considering their fluff, but end up being significantly worse than other classes in play. And this disparity actually widens inexorably as you go further and further into the campaign, until other classes are actually strictly better than your class at every single aspect of gameplay. That's just crap.
So balance is separate from but related to fairness. Fairness in itself is more necessary than balance in itself. Balance is a sort of brute force tool to ensure fairness, but is not the only way and in fact is often the most boring way.
But of course, balance can be important even when it's unrelated to fairness. Even in a totally fair situation -- let's say where you're rolling for ability scores that are extremely important to character effectiveness, and maybe lock or unlock whole classes -- it might simply be too swingy so that people get pissed off and disengage.
So balance should be sought to the point where people stop getting pissed off and disengage. But no more, because balance beyond that point has no perceptible effect and can only eat away at the fun brought by other elements.
Just trying to inject a little nuance into the balance discussion.