Cool cartoon introduction! I’ll quibble with them on one point: they say "It’ll decelerate from 13000 mph to 1000 mph, pulling about 12 'g’s in two minutes.
Actually the average acceleration over two minutes for that would be around 45 m/s^2 which is about 4.5 g. So either one or more of their numbers is wrong, or else (and this is quite likely), the acceleration might briefly peak out at 12 g at some point during that two minutes, but only very briefly if the average of ~4 to 5 g is to be accurate for the entire interval, the rest of which would have to be spent at less than 4 g.
So a 70 kg human would only weight about 3200 Newtons (~700 lbs) instead of the crushing 1800 lbs they indicate.
Click here for a highly scientific depiction of what such hyper-gravity might feel like. [Warning - there may be one or two slight scientific inaccuracies in this depiction too.]