Its not just simply believing something. I'm talking about millions of people all around the world with JOBS that use space and earth's curvature that lives depend on to function correctly. There are satellite manufacturers/operators, software designers for all the satellites, atmospheric scientists to predict weather and warn cities of dangerous conditions, jet stream technology, propulsion engineers/ ballistic missile guidance engineers that can send missiles into space to attack another country
In Field Artillery the rotation of the Earth is taken into account when they shoot something:
Manual that shows that in Field Artillery the rotation of the Earth is taken into account. They have to correct for the vertical (range) and horizontal (azimuth deviation) components of the Coriolis acceleration.
walter.bislins.ch
Bridge and tunnel builders have to take the curvature of earth into account for long projects
new.mta.info
If the Earth is round, some large human-made structures should have to account for the Earth's curvature. Do they?
www.spacecentre.nz
Fiber optics cables are designed to take the speed of light into account.
There are no flat earthers that work at any of these careers because flat earth logic would not function in real life technology