I don't mind at all, but it's frustrating that you so easily conclude that you are right when you are so clearly and demonstrably wrong.
The undeniable fact is that you are the one who is clearly and demonstrably wrong.
This is why we repeatedly have said "show the build" "name the encounter."
Any sort of showcased build or encounter is always going to fail the "three strikes" rule of theory-crafting:
1) The build always assumes that the character is at full power. This tends to only be true for the first encounter of the day (which, even if you stick to the whole "four encounters per day" paradigm, is only 25% of the time). So the vast majority of the time your character will already be down on hit points, consumable materials, spells, etc.
2) The build assumes meta-game knowledge of the encounter before meeting it. Simply put, this presumes that the characters already know what they'll be facing, and have arranged their spells, feats, magic items, etc. so as to be perfectly optimized to defeat it. This is another area that's divorced from how things are in the game world.
3) The build assumes that everything revolves around this encounter. This is really an extension of the second one, but shows how such builds are the product of tunnel-vision. Yes it's useless to have a
helm of underwater action if you're showcasing how your character can one-shot a balor, but there's a reason why a character that's used in a game will have one, whether from what they were doing before, or (think they) will be doing later.
So you see, requests for "show me the build/encounter" are not only a waste of time, but are asking the wrong questions from the very beginning.
You've clearly never played with anyone who ran a competent full caster, particulalrly not one who tried to fulfill a melee role. Also, clearly you've never solo'd a high level fighter against a variety of CR appropriate challenges with a competent DM (neither have I).
You admitting that you've never done these things completely undercuts the legitimacy of asking them to begin with. I've had full casters in my games who were "competent" in that they helped win the fights they were in - apparently, taking damage-dealing spells makes them "incompetent" despite the fact that they were contributors to the encounter.
It's not about optimization, it's about versatility. The high level caster has the versatility to handle any CR appropriate challenge and to fulfill any party role, the fighter does not.
See above. This idea that wizards can handle anything fails the three strikes rule.
The answer of "I have a magic item for that" is, in fact, a cop out because the full caster has the same WBL as you and so has the same amount of magic item "answers" - more, in fact, because they don't need an upfront investment in weapons and armor. In ADDITION, they have spells, and all they lose is BAB, HP and feats.
First, saying that "all they lose is BAB, HP, and feats" showcases the tunnel-vision I've been talking about this entire time. Secondly, I've already explained why it's not a cop-out, please re-read the above post. Third, having magic spells in addition to items is only useful if those are the right spells, and they can successfully cast them - in this regard, they might have slightly greater potential, but that's meaningless if they can't actualize it.
So, 10 points of BAB, a bunch of HP and 6 extra feats (11 fighter bonus feats - 4 wizard bonus feats - summon familiar) vs:
4 zero level spells
4 1st level spells
4 2nd level spells
4 3rd level spells
4 4th level spells
4 5th level spells
4 6th level spells
4 7th level spells
4 8th level spells
4 9th level spells
Just think about it. Shapechange. Wish. Gate. The list goes on and on.
See? You're already falling into the trap of assuming the build is the most important part.
Or consider a melee druid wild-shaped into a dire polar bear with a tyranosaurus animal companion summoning elder elementals.
Or a cleric...
There's just no comparison.
And I like melee characters. They are fun. But I am not so naive as to not notice that I am only surviving due to support from my casters.
With any luck, I've helped to dispel some of the naivete you had regarding this. Spellcasters can theoretically be powerful in a given challenge, but that's the thing about theories, they don't always mesh with reality.
