Flat earth is quite a rabbit hole for many people. I wonder if they are so wrapped up in it that it becomes part of their identity making it very hard to let go, to the point of being intellectually dishonest with themselves.
A few of the big players in flat earth are known to be dishonest. For example Bob Knodel who featured in the gyroscope experiment you mention was previously caught out lying about being an professional pilot (and his claim of being an engineer is probably also a lie). I suspect there are also a lot of people in it who are not really flat earther's but are doing it for attention/views, etc.
From what it looks like in that film, yes, it becomes their identity.
Gradually their friends and family no longer see John Smith, but John the flat earth guy. If they then reject their flat earth community, regular society is hesitant to accept them back.
Some of the people in that film, I was looking at them and thinking "if it wasn't for flat earth, you'd be alone and definitely not famous". And it is truly sad to see people building communities around and worshipping a poor understanding of science.
It reminds me of when butters from South Park sets up a church in his local DVLA office 😂
Posted using Partiko Android