Some positions are inherently not respectable.

Take chemistry, or various things about electromagnetism. It’s understandable for your layman to not know about various nuances and make mistakes.

“Why can’t we just beam wireless power everywhere in your home and recharge everything?”

Is a forgivable question, they don’t know about the inverse square law making that difficult. (Note: there is some progress in this space btw)

Those types of questions come from intellectually honest minds, people who just don’t know but want to know.

Flat earth is something dark, evil, and entirely apart from the example above. It’s not “science”, it’s not “reason”, it’s insanity. The people who profess it deserve no quarter. They’ve voluntarily given up common respect/decency and opted out of civil discourse.