I'm honestly not so sure it's "easily" disproved. A lot of what I've seen so far for debunking it seems to be based on (inaccurate) assumptions for what flat earthers believe or using scientific theories as proof (ie gravity) or just having to believe what we've been shown from a relatively small set of entities.

For example, being able to see far away objects that should be completely obscured by the curvature of the earth, such as a mountain range hundreds of miles away where even the peak should be hundreds to thousands of feet below the horizon. The globe explanation is that it's some form of light refraction or bending but for 99% of people that explaination relies on the testimony of a specialist and is not something a layperson could prove.

And just to be clear, I don't think the earth is flat, I just think its interesting that I've yet to see anyone who CAN understand and explain the physics and mathmatics of all this take the time to understand what flat earthers are claiming and show how it's wrong in a respectful way.