I believe the mainstream view of the world being spherical, but admit that I have done no experiment personally to prove so, because it is unnecessary when others have done so (although that too has no proof). If everyone went around believing nothing until they proved it themself (except conspiracy theories, no proof required for those), then everyone would be insane basically. Time zones are evidence of not a flat earth with a stationary sun, and if there is a rich flat earther somewhere, they could go on a cruise and measure the speed and time to go from the Falkland Islands to South Africa; their most common theory which claims that the
Azimuthal equidistant projection is the true shape of the earth would make the time be increased, but they would just say that they were drugged, or the boat went faster than all evidence said it went, or aliens/Bermuda triangle teleported them. They could travel to Brazil and take a road trip and measure the distance via the car, but would say that it was designed to change the amounts to fit the government's idea. Even if there were little evidence for a spherical earth other than television, telephone, internet, gps, and weather prediction (satellites), there would be plenty of evidence. And one of the harder ones for the flat earthers to answer: WHY would they fake a flat earth to be round, what benefit is it? Why has no government leaked it (okay, go ahead and claim they have but the ones where we are blocked it...), not even North Korea, which leaked a crewed expedition to the Sun
? Why did they not fake the moon landings more? Why did they not censor all of your youtube videos and comments? Why did they not fake a mission to Mars?