> religious people often conveniently shift goalposts

It isn't "shifting goal posts"...It's called updating your beliefs when the evidence proves them wrong. Many religions have a strong history of doing this and it is something that flat earthers don't do.

> Flat earthers do almost the same thing just they use conspiracy theories instead.

If you don't understand the epistemological difference, you should try educating yourself. There is quite a bit of scholarly work on this...