Scam is a global issue even before crypto, I think some is just saying that crypto is all scam since it's done in the internet. And as we all know scam normally happened using the internet thus, most people think it's scam. I think whether it's crypto or not, scam is inevitable because scammers just can't get off their hands to easy money.
Scammer did scams with fiat and bank accounts etc and now they are scamming crypto also. Everything which has a value is subjected to be exploited by the scammers. Saying that scam are only because of crypto is wrong.
Scam is a problem for everyone, not just for cryptocurrency. You right, scam exists not only on cryptocurrency, but on any transaction that can be misused and exploited by a scammer. So stop to justify that crypto is a scam only because of the actions of some scammers