[why many of so-called blockchain projects these days are scammers
are you referring to shitcoins and it's ICO and Crypto Exchage and it's IEO? if so, then it's all about greed and opportunity there's nothing more.
is this was motive behind the technology?
No, the motive of the technology was to separate bitcoin from any kind of authority/government making it decentralized and free to use to everyone without boundaries.
many real investors are not confident to participate due to fake blockchain projects all over the internet.
They are not afraid they are just being cautious and if there is a promising project you'll see investors lining up for it.