I think categorizing people who look at the numbers as being unfamiliar with gaming history to be dangerously short-sighted.
Sure, there are likely to be some who have only started playing with 3.x. But I would caution ascribing the majority of such players to that category.
It's as dangerous a position as saying that the people who think that looking at the numbers are johnny-come-lately people who got their start larping in the park and scaring all the neighbors with bad hair and the smell of cloves.
Both are equally inane.
Also, I hasten to add, are arguments that say that powergamers are the minority of the gaming populace or that larping interferes with math skills.
Empirical data showing your gaming statistics argument or it didn't happen.
In any event, there's a reason why tier discussions have combat as a major (if not *the*) component.
A large part of D&D is about combat.
And the combat discussions tend to revolve around the numbers, because the numbers are empirical.
Let me give you a demonstration.
Everyone, please rank the classes by tier, in terms of role-playing potential.
I rest my case.
Hey, let's face it - D&D has always had combat as a major (if not *the*) component to the game - one could argue that as time progressed role-playing become more prominent than in the beginning (which I think is a good thing).
You can define the tier system to be utility over combat capability - hey, that's your right and if you make it clear at the outset that it's your expectation, then I'm all for it. I think part of the problem is someone says "tier" and a lot of people think "combat tier" while others think "utility tier" and then they start arguing definitions instead of realizing they have two different arguments. Heck, throw in some more "x tier" discussions too (such as "self-sufficient tier") and IMO, you make for a more productive discussion.
Y'know, any class can thrive in any campaign. The factors that go into it are the same - rules, GM, player, luck.
The question is to what degree much one of those factors compensate for another.
I started out a long time ago and I rarely let the rules get in the way of the story (note: I didn't say *my* story) - but I'd be lying if I told you the rules never got in the way of that story and often an area of rules-weakness are the classes.
I noticed this the most with a recent Kingmaker campaign - the encounters are built according to the RAW and they expect characters to have certain combat requisites.
That's not a subjective opinion, that's part of the core of the rules set, and yes, combat numbers are something that are very important. (I again suggest people who are so bad at math that they have to role-play* drop $5 on a copy of the Trailblazer PDF to understand the fundamentals of the mechanics - and why it's important to know them.)
*It should also be noted that people who are good at math are out role-played by a pet rock, which is why they do the math.**
**Obviously failed attempts to insert levity.
Look, the main thing is that, IMO, you shouldn't ignore the basic math issues any more than you should ignore the role-playing - they are part and parcel for the game. At the end of the day, the most important thing is that you spend some time with people you enjoy spending time with, while doing something you enjoy. And the same for the other people.
tl;dr - The more tiers, the fewer tears.