They aren't a laugh as I explained to previously.
Well please show the results of your "candle experiment" because even the best strength/weight ration "thread" would sag more than 10 times the curve of the Earth even at twice its rated load.
So your "candle experiment" is a joke!
Your "shipping crate experiment" is little better because even if the top of the crate is 30 feet above water level the dip to the horizon would be only about 0.09° so it would show next to nothing.
And once the sun showing was 20% of its diameter the top edge of the Sun would be level with the top edge of the crate.
Putting your crate on a 1000 foot mountain might show something!
So, yes those two are jokes, so what's next!