I don't think that it's scam Behind BTC is very strong technology called blockchain.In my opinion bitcoin is proven legit.
Bitcoin is often called a scam or a pyramid by those who did not buy it, for example, for $ 100, and now, watching the current rate, bite their elbows and console themselves with the fact that "all this will collapse soon." Another category of people who consider Bitcoin a scam is those who have a bitter experience in dealing with cryptocurrency fraud. Some guys, due to their lack of education, do not even try to understand what trading is.
Not only is Bitcoin called a scam or a pyramid by those who did not buy it, but also by those who bought it and sold it only for the price to sky rocket to the moon and they couldn't get back in. Also, by those people who don't understand it, who think that it's some random fake digital currency but don't understand the underlying blockchain technology. To be fair, most people aren't experts in it... but we understand the point of it.