Only because scammers use bitcoin doesn't mean that bitcoin itself is a scam! If someone wants to bad mouth bitcoin he will of course use this argument, but there are unlike larger and more scams based on fiat money!
The fiat money itself is a scam as only some privileged banks are allowed to control and create it while everyone can create bitcoin and no one controls it. That is a huge difference!
AH! Thats like good comparison between fiat and to let know how bitcoin is worth more than just a scammed scam! I mean people around the world get jealous of many things if they are not achieving any success with something and then they will blame it for sure. In case of bitcoin same thing happens and most of the time people are confused how to earn bitcoin, where to work for it and where to spend it. If this continues then then they will call it scam out of the frustration. So I believe there are lot many more people who don't like bitcoin for persona reasons but make it public.