The difference is that flat earthers have to go through such massive logical contortions to support their claims. Not to mention the idea that every technology company and government is coordinated on a massive cooperative conspiracy without any substantial leaks is laughable.
I'm not sure what research you are referring to. There's plenty of research I have available to me about astronomy and past endeavors to not only prove that the Earth is round, that people have been off the planet and that we have explored the galaxy enough to prove the earth is not flat. The only research I have not done is personally gone to space.
So are you saying that it's not real research unless I go to space and see for myself?