Most of the things you've listed here are not problems that occur exclusively with Bitcoin or cryptocurrency.
These are just things that happen due to human nature, so unless you can find something that would make human beings less greedy, I don't see how this can be fixed.
It might be a bit negative of me to think this, but I really don't see how you could completely eradicate scamming and cheating.
Maybe in future societies things like this won't exist anymore, but it'll take a massive shift in attitude to solve it.
There are countries where you see extremely low crime rates, Japan comes to mind, but crime still exists even there.
yes in this case i agree to you .. nothing will change because greed and selfishness is indeed human nature. little solution is already there like america that has made kyc rules for investors and buyer tokens on first sale .. and lately there are some exchanges that try to destroy and manipulate the market so that the investors suffered big losses with prices far below the ICO, I think some of these exchanges must be followed up to legal entities .. if indeed they want to release a token they must first make a contract with the developer. I personally feel this .. finally I was afraid to invest at the beginning of the sale.