I’ve squatted barbells since roughly 2006 and the feeling of having more than 100kg on your shoulders is very intense, even if you’ve trained up to it. It feels like it’s crushing your whole body and even breathing is hard.
The idea that an untrained person could put a 180kg barbell on their shoulders and be comfortable AND move around is laughable, they would collapse very quickly.
Seriously, go and try it, load up 100KG or roughly 225lbs on a barbell and just stand there with it. If you're already a big/heavy/trained guy, put 180KG or 400lbs.
It will probably be quite a surprising experience for you.
And I will say, that even when I was training for heavy squatting, standing there with a very heavy barbell on your back isn't fun at all, you have to have a very tight core, tensed muscles, breathing is much harder. i.e. just standing there is hard work and you want to get your 5 squats done asap. Also, it just plain hurts your back as the metal bar on your spine is painful!
Could they use a machine to load up to that point? Cushioned and loaded in a way that doesn't use traps/a barbell? Maybe.
I say this as someone who deals regularly with weights around that level, at a similar weight.
Having said all that, I do 100% agree that loading your back and getting the weight there are two different things!