Then you should know - your argument is burying the useful word distinction and meaning in a not-completely-incorrect, but not-useful-in-reality wrapper.
Yes, there is always a degree of myth in common usage. Yes, there is always an element of distortion in history. And the further we go in time, the more history turns into myth as actual evidence gets lost, buried, destroyed, manipulated, etc. And history gets manipulated for political purposes.
But there is a giant valley between the common case of myth, and any formal study of history. For real reasons, because there are fundamental differences in approach and goals. Think 90/10 one way, 10/90 the other way (hopefully).
Because any study of history which isn’t solidly based on actual independently verifiable facts or evidence isn’t history, it’s just myth making. And those are different words for real reasons. Including trying to fight manipulation and BS. Something that is really important for us to remember, especially now.
Because at some point, something either did actually happen or not, and for folks who care, that matters. If people don’t, that’s fine - but let’s not confuse anyone by confusing the resulting cool stories with actual history eh?
There are many aspects of what we call "history" that are guesses, best guesses, biased guesses, ignorant assumptions, intent-driven narratives, or uncontested acceptance of plausible but currently-uncorroborated narrative.
It's a mistake to pretend that any "historical record" is not littered with these things. More so as the years tick by, more so if there's any contention around influence or meaning of the person/story. (Aside: This is why I will not watch Oliver Stone movies.)
There is (usually) a bright line between truth and falsehood. We almost never know where that line is.
Sure, some details are documented and plausible. These are probably true, unless there are details that are very important or useful to some group.
And some details are incredible and fanciful. Probably "false" although possibly derived from some kernel of truth or substantively true but simplified/embellished for audiences over time.
The deeper you dig, the more you realize that all stories are incomplete at best, and likely several layers deep in manipulation or at least imperfect interpretation. We are all imperfect interpreters.
Do I believe that Caesar crossed the Rubicon in 49 BC? Yes -- with very high certainty.
Do I believe that he uttered Iacta Alea Est just before doing so? Maybe -- it's romantic and flatteringly displays his executive strength, and IIRC he wrote that he did.
If you want to delineate "history" from "myth" on the "truthy-falsy" spectrum, you may choose to do so with that example. But this history and mythology are inseparable, so the distinction is untrustworthy and often not useful anyway.