> "You can recreate the effect you are talking about over a small body of water"
Um, no, you can't. If there's no curvature, then there's no hiding the bottom of the boat before the top. It's just that simple. I see nothing in your video that is evidence otherwise. (Not to mention the scale would be wrong.)
I can't shift any goalposts on a single claim. A claim that I am confident making, by the way, because I used to live near Long Beach and saw ships pulling out of LA's largest harbor daily. They always went 'over a hill' on the horizon, and never, ever, just kept shrinking until gone.
I won't try to 'steel man flat earth and geocentric positions.' It's not worth my time... But I can stand by a statement I've made and encourage you to verify, not trust, like I would to any would-be bitcoiner.