If you correctly explain about Bitcoin, then hardly anyone would consider it a scam. First of all, in my experience, it is difficult for people to understand how something intangible ("what??! digital money??! wtf??!") can bring real money. That is what needs to be properly explained.
Next, acquaint with the history of the creation of Bitcoin and tell about the reasons for its appearance, about what problems it can solve. It is necessary to show how much people benefit from the fact that they pay something in Bitcoins, rather than using traditional bank transfers.
And only after the person realizes all this and understands, it makes sense to talk about the cost of Bitcoin and that its price can vary greatly. I think if you, as a person who wants to tell people around him about Bitcoin, really believe in Bitcoin and in his future, then you will find the right words to convey your faith to the people to whom you are telling about it. Good luck!