What it's got to cryptocurrencies the derivative form of speculative assets based on blockchain ?

Speculative assets aren't what drive or not drive adoption. They can get attention, because of spikes in value, but it's not what drives it. Blockchain is a distrubuted database something known for a whole lot more time then you can think, just it's now a nice buzzword.
And it has very limited uses, because of decentralization and thus being slow, unless you centralize it and then you have normal database with buzz "blockchain", like with EOS, ripple or NEO.

Yeah, go on, we need more swears, until you got banned.