People can say scam about things they don't know. They heard about Bitcoin late, and when they realize they were late, they say it's a scam. They heard about Bitcoin at the time but wasn't interested in it, they had to watch the whole rise without coins in their hands, they say it's a scam. They didn't understand what Bitcoin is and didn't research it, they think it's a scam based on what they heard from the media and their environment. These examples can be multiplied. The important thing is not what people think. It is what you have learned, what you have added to yourself, your curiosity and research on technology, and knowing what you are investing in. Don't blindly defend or criticize something.
I totally agree with your opinion, especially in countries that don't know much about Bitcoin, the media in those countries spread negative information about Bitcoin, so the people of that country have a negative opinion about Bitcoin, and because of this, most of the people are against Bitcoin and promoted as a scam currency.
Especially if I talk about my country Bangladesh then such idea is right because the media and news papers of my country spread negative information about Bitcoin and as a result most of the people in my country think Bitcoin as a scam booster. Moreover, central banks in my country give wrong information about Bitcoin, so big entrepreneurs know Bitcoin as wrong platform.