“And I will establish my covenant with you; neither shall all flesh be cut off any more by the waters of a flood; neither shall there any more be a flood to destroy the earth.” - Genesis 9:11 (KJV)
Isn’t that kind of like saying that “I promise that I won’t shoot you again.” But simply stabbing the person with a knife later?
I take it more as a promise that God won’t do something again that would eliminate the vast majority of the population, the flood was just a means to an end.