Of late I've been taken by the concept that someone who grew up on the far side of the Moon, and never travelled very far, would - due to the Moon's rotation period equalling its revolution period - be completely unaware of the existence of the Earth. They'd see the Sun rise and set in a 175 hour cycle, along with the rest of the Universe. The notion that a brightly reflective body, significantly larger than their own spheroid and covered with billions of intelligent (?) beings, existed a mere 238,900 miles away would be absolutely preposterous ... at least until said resident travelled far enough to peek around the horizon and see a most mind-blowing sight.

I mention that to set premise that one can be remarkably unaware of a plain truth just around the corner. The strong argument for Earth being flat is little different from the strong argument for Earth perceived as flat. The flaw obviously is the objective difference between fact & perception.

I go thru trouble of writing this to note that while you're pointing fingers at the difference between being and perceiving, you are yourself holding the mistaken notion that Earth is a lumpy sphere, when Earth is, in objective reality, a very long and slightly bent 4-dimensional _spring_ shape, which we see just a 3-d cross-section of which looks spherical to us lower-dimensional beings.

While making a strong argument, be humble - your perception may be objectively wrong, misguided, or incomplete as well.