Lots of people are now wise up and aware about such scams, any investments schemes that promise to double your investment within a short period of time is mostly to be a scam, they were rampant around 2017-18 when lots of people are not aware about such scams, currently, only the greedy ones that will fall for such scams
I am sure people can search for more news to find scams or to know if that is a scam or not. But yes, people already get many experiences related to the fraud itself, and that makes them careful to choose the investment from the projects. They will invest in the project after they can get so much information related to the project, so they don't get another scam. Besides that, they have a good lesson on how to avoid the scam, and they will tell their experience to other people too.
That is some of the problems some people are facing, they are lazy in doing thorough research about what they wanna, no matter the experience a greedy fellow had experience he will still want to invest in a ponzi scheme thinking that he's gonna hit it big
Moreso there are some projects that looks good to be true, they will have good website, team, and at the end of the day they end up being a scam project,