Scams are everywhere and it's very easy to implement a project scam in the cryptocurrency world because it is being done on the internet. The Internet can be used as a tool of scamming people especially when people get attracted to profit. Since then, I encountered a lot of scam projects for not paying the bounty hunters or the participants of the said project. I also participated in debunking a scam project to its lack of proof of legitimacy.
It's a big issue and very hard to be solved since it's being done globally and we can't control it instantly.
Negative stigma is very inherent in the world of cryptocurrency, and until now that is why some countries do not legalize crypto as a means of transaction but only in the commodity futures category.
Also because in the world, there isn't really much money to go around. Banks to Banks and those 3 big boys, its all about passing around paper with signatures on them. that's it. now this similar stuff is coming forth digitally.
Decentralized cryptos cannot be printed above the cap values so once it reaches maximum availability then people have to use only the available cryptos but the value will greatly oncrease when the demand gets higher so we already have a perfect system to restrict the paper money but not many people still don't get why we need crypto currencies.