First of all, I don't understand the conversation you were having with yourself in the first part there. Both TSR's and 4e's solutions solve the problem, they just aren't popular. Personally, I felt 4e's method made magic less cool because it worked exactly the same as not magic, but that's just my preference.
Secondly, I agree that multiple options should be supported. But unless there's some verbiage in the book that makes it clear everything isn't core simultaneously, people will assume it is, especially if it's in the main book, and you'll have that extra fun experience of explaining to your players that they can't use everything in the PH just because it's there.
In reverse order:
IDK, I have no problem with that conversation. "This is the setting & campaign I want to run, these options fit it, these others don't. Would you rather play something else, I have quite the backlog? Or one of you could run..." "oh? No? OK...."
But, yeah, the point I wasn't making too well, was TSR didn't fix the martial/caster gap - it had balance, of it's own sort from the beginning... magic-users were under-powered and fragile at low levels, wildly OP at high levels, and in-between the grew from contributing to dominating. Overall, the whole MU experience, was arguably balanced.
3.0 broke that by making Casters OP all the time.
So, this is my problem: the implication, in your post and that of the OP, that those of us who don't agree with your position must be stupid, confused, or lying. Is it even remotely possible that intelligent people might have the same facts as you and come to a different conclusion?
That's why this argument keeps going in a cycle: instead of accepting that their opinion is just an opinion, a lot of folks comes from a place of absolute rightness and won't accept the possibility that they are wrong.
My opinion might be wrong. But you aren't going to convince me by insulting me.
Insulting eachother, even being impolite, is against the CoC. Being stupid, confused, or lying, is not.
And, no, I don't agree that's the implication. There shouldn't be an implication about the people making an argument, the argument should be judged on it's merits. The OP pointed out a potential flaw in reasoning, whether it meets the definition of a fallacy or not, and tried for a catchy label.
Anyway, yes, intelligent people can look at the facts of the Martial/Caster Gap (itself, just another catchy label) and reach different conclusions: that it's not a problem, that it's a highly-desireable feature because casters should be superior, that the DM can just compensate for it, or that it should be fixed in a variety of
very different mutually-incompatible ways that may well cause issue of their own.
But just denying it, like, "no, casters do not get a large number of varied and powerful daily resources" or, "sure, but martials also get a large number of varied and powerful daily resources?" No. Nobody does that.