Surely if some combination of weapons and armor did not generally exceed the performance of being unarmed an unarmored, people would never have bothered with the stuff.
Which is why the fantasy the monk promises is enticing to people. It fails to meet that fantasy though, which is a problem.
It seems to me like the basic "problem" here is that Fighter is just a much more conceptually broad and flexible class than Monk, which works within a much more limited theme. Under those circumstances they'd really have to put the thumb on the scale for Monks for a Monk, built towards pure mechanical optimization within the limited conceptual space of a Monk to not be exceeded a Fighter, similarly built around pure mechanical optimization within a much broader framework.
Yes, if you mean giving the Monk a chance to be as good or better than the fighter within their space, then that is what they should have done.
Put a Paladin and a Fighter side by side, and it is nearly impossible to determine which one is "better" at level 1. They are doing basically the same things.
Put a Ranger and a Fighter side by side, and it is the same thing.
Put a Barbarian and a Fighter side by side, and the barbarian is going to be doing less damage probably, but they are much tougher, and so it works out pretty nicely.
At level 1 the monk (without the nick exploit) is not doing more damage than the fighter, they aren't tougher than the fighter, they aren't faster than the fighter. They lack spells and abilities almost entirely. They are... generally just weaker. And that is a problem.
Heck, Monks get compared to Rogues a lot. The rogue will have 1 less AC, massive buff to out-of-combat skills through expertise, and be capable of dealing 3d6+3 or 13.5 damage on a turn. Basically the same as the completely unarmed monk.
I don't need Monks to do more damage. I'm okay if their AC stays as is. But they need a little more HP, and they need something unique beyond "if we are captured, stripped and enslaved, I can still fight!" for a class identity.
Now whether D&D should continue to have a singular, catch-all "Fighter" class covering so much of the "didn't fit in any of the other, thematically narrower martial classes" design space is another question.
You are right, that is another question, and not one we are discussing.