I searched and found it, thank God. I still have some secondary questions:
1. Is most of the world today not obligated in the seven Noahide commandments—because they are not descendants of Noah?
2. Why does M indicate that there was a flood (in the Black Sea) in 7500 BCE, while the flood story was around 2700 BCE—much later than the geological finding?

It's worth asking M. I haven't dealt with this. I'll refer the question to him.

1. There was a kind of flood (local) in the Black Sea thousands of years ago. That flood was probably the one on which all the known flood stories in the world were based.
2. The Torah, which lived in that same environment, also decided for educational reasons to take those flood stories, which were blatantly immoral (for them the flood happened because people made noise for the gods, whereas for Noah it was because of moral corruption), and adopt it in a more moral version. Therefore the Torah places the adopted myth, for educational reasons, within the time frame convenient for it, and not at its exact historical time.
3. Therefore, one can say that on the one hand the Torah's purpose in the flood story is to contend with the local myths, and on the other hand in this case it turns out that even this myth is based, at its core, on a true story.
4. "Children of Noah" is a designation for all humanity.
5. Even though the Torah speaks about a worldwide flood, there are also several places that hint that there were areas that were not in the flood.
6. Not that this is interesting in itself, but since you only asked "whether it can be said," I'll share that there is a *very* well-known rabbi in the Religious Zionist public, considered conservative and a teacher of thousands, who once told me in a private conversation that this is also his personal view. He avoids saying it publicly solely because it requires maturity on the part of the listeners, and people are quick to attack what they don't understand as heresy.

It's a bit flimsy to run away every time to the claim of an educational myth and take the text out of its plain meaning. There are detailed descriptions. What's to stop us from saying this whenever we feel like it, and why isn't it simpler just to assume that the Torah claims it happened, but it didn't really happen?