concave or not, there's one thing for sure: WE DON'T KNOW what the shape of the Earth is. There's not enough publicly available evidence to even support the Copernicus'es model. The important question is --- why are we being deceived and who is deceiving us?
Agree with you...sorta... , but you are defeating your own message by discussing a concave earth in any real sense other than one of many ideas.
We don't know the answers, however, we are not being purposely deceived, we are deceived by the arrogance of man's limited mind and by the sheeple mentality of the vast human population.
We want to have answers, we want "smart" people to provide them, we trust and build more answers upon their "facts". In the end we have a model of the world that is fiction but real enough for 99.99% of people on the planet.