No, I understand. "Balance", as a term, is pretty much meaningless.
It gets bandied about in different ways (including some that are essentially 'straw men'), but that doesn't make all of those ways meaningless, it's just a little confused - and, of course, some people are against it.
If someone feels that balance "over the campaign" is balanced enough, they're not going be able to have a discussion about game balance with someone who bases balance around DPR calculation per level. Or if they prefer everyone has a job to do "spotlight balance" over everyone has a role to play in every phase balance.
I did see a definition of balance (I don't think it was in reference to RPGs) that I liked & remembered:
A game is better-balanced the more choices it presents to the player that are both meaningful and viable.
It's a higher bar than it may seem.
Take the common thought-experiment of the 'perfectly balanced game,' with no options (coin-flip dungeon) or no difference among options (rock/paper/scissors). Not balanced at all under that definition.
Or consider the classic-D&D balance-of-imbalances-over-levels scheme: your magic-user is wildly overpowered at 18th, but that's 'balanced' by him dying at 1st level, because he only had 1 hp, and was attacked by a house-cat? What if he's rolled a high con & good hps, and was not killed by a house cat? What if the campaign peters out at 7th? What if you roll a low DEX and can /only/ build a Cleric? Does that balance your arch-mage because you didn't get to play him? Do the times you play a fighter because you didn't get a 17 CHA 'balance' the time you play a Paladin?
The real tension point, I feel, is determining what elements of the game must be mathematically imbalanced in order to create a specific feel, and where it's impossible for the game to cater to the concerns of both balance-oriented and feel-oriented players.
I'm not sure I believe that there is a tension between balance-oriented and feel-oriented players. They both really want the same things, they want a game where they can play the character they want, and have the experience they expect, and generally enjoy the game - and don't begrudge others the same. No matter how 'feelie' you may be, you /probably/ don't want the 'feel' of dominating play and keeping anyone else from having any fun all campaign long, for instance.
You're definitely not.
I get what you're saying when you say 5e is ore art than science, Tony. I probably grudgingly agree. It's not like my group isn't having fun and I will admit I am enjoying bending rules more in this edition than others; it has indeed captured a sort of nostalgic feel for me (2nd edition, in my case, though I played plenty of 1e).
Nod. In my case it's 1e.

I ran a 10-year AD&D campaign, spanning 1e & 2e, and I ran so much of it in an improvisational style, exactly like I enjoy running 5e, today.
Especially as the campaign reached higher levels.
Having said that, I assume professional game designers have skills, experiences, tools et al. that I don't when it comes to game design. I also assume that subsequent iterations of a game clean up things that didn't work before. This is why people like myself and Zapp (and others, I am sure) are genuinely perplexed that the latest edition isn't 'tighter' when it comes to the "science-y" aspects of the game (which necessarily includes encounter-building based on CR, one of the more high-end math parts of 5e).
Just because I see 5e and 5e DMing, in particular, as 'more art than science' doesn't mean I think the two are mutually exclusive. You can have great art that's amazingly technically precise, bordering on 'perfection,' (the Mona Liza, Mozart symphonies) and you can have great art that adheres to no technical standards whatsoever (ee comings, Jackson Pollok). You might get a little more push-back on the latter, I suppose, but that's art for you.
After staggering around the map for 40 years, D&D realized it /couldn't/ afford to get it's act together, and had to be true to all the extremes it'd blundered into over the decades. 5e is the result. It's technically...
...well, it has artistic merit.
It can be more art, sure, but the math and the science should be tighter, IMO, and it falls apart at higher levels. I suppose "I love how DnD never works properly at higher levels!" might be a form of nostalgia, but...
Yes, and it's legitimately part of the classic feel, which 5e, equally legitimately, has striven, successfully to evoke. Doesn't mean you can't patch it up, though. If you patched it up in the past, and patch it up similarly now, that's not just classic feel, that's classic feel /specific to your experience/. Now that's nostalgia!