It really is. How have people not realised that flat earthers simply do not care, and are far too busy having fun to care about what some dork measuring shadows has to say?
It's the trying to pwn a bunch of people who have consistently shown that they don't care that I find weird. Like the old anti creationist debate bros back in the early days of YouTube.
The science is very interesting and fun, but the context in which it is framed is just sad.
Because they’re delusional anti-intellectual weirdos and dunking on them is fun.
Back when youtube was 6 months old, it was quickly becoming overtaken by Christian Creationist preachers and other such pseudoscience peddlers. They ranged from well-funded organizations with hired production crew, to lone individuals talking to a webcam. This led to a massive surge for various movements like flat-earthers, creationists, moon-projectionists, moon-landing deniers etc, with the pinnacle being a very successful funding campaign to build the Creation Museum in Kentucky. As a reaction, a lot of scientists and atheists started making their own channels to challenge them. For years this was a big part of Youtube, and whatever remnants have been left from that era still pop up here and there.
Thunderf00t is one of those atheist channels that appeared back then. Check his earliest videos and you'll know what I mean.
I found a YouTube link in your post. Here are links to the same video on alternative frontends that protect your privacy: