I'd like to attempt to reset the debate. I have not been involved in the clash of ideology between Flat Earth and Round Earth proponents for very long. Frankly because I had never realized it was even a thing.
So rather than focus on what we disagree on, let's attempt to compile things we can agree on.
On the wiki, The Bishop Experiment used Google earth to measure the distance between Monterey and Santa Cruz.
Let's begin from there and try and agree on distances between locations?
You're heading up a blind alley.
The problem with looking at things disappearing over the horizon is twofold:
* You can't do it over land because terrain is bumpy.
* You can't reliably do it over water because the temperature inversion over the water and rapid changes in humidity with height result in a mirages and other optical phenomena that can never result in a decisive answer without a LOT more science. Since that science is never going to happen - this is a bust.
If you want to finally come to conclusions, you have to look at the environment around the Earth - the stars, moon and the sun.
* Sunrises and sunsets, moonrises and moonsets.
* Phases of the moon.
* Orientation of the moon.
* Motion of the stars.
...and you have to do these observations at widely separated points on the Earth - especially the southern hemisphere/hemiplane.