Wow ExEK, your comparison to rape is quite repulsive. There are dozens of other ways to phrase your example without reaching like that.
Basic due diligence would include a Google search. I did this at the time the whole scheme was starting to be talked about on board. Within two clicks I had the previous scheme/company name and pages a mile long full of people warning they'd been scammed by Tadawul/Exential.
So yeah if people couldn't be bothered to Google at least then they do shoulder some of the responsibility of a bad investment for not taking less than 5 minutes to check.
More responsibility belongs to those who were aware, yet convinced others who may have been wary to join by abusing their power dynamic (more senior crew to juniors, for example)