Please don't compare wilting flowers to an advanced technology that can protect people from the bad intentions of banks and governments, along with many other potential advancements for human kind.

Blockchain is the real value, and it's not going away, regardless of what you think about cryptocurrency as a whole. The technology is undeniably powerful, and projects like Polkadot are enabling real projects to come to life and outlive crappy Dapps based on things like Ethereum (I'm a frontend dev who works on the blockchain, btw).

If blockchain isn't going away, then cryptocurrency as a whole isn't going away either, although many alt coins will bite the dust as you say. Invest in some DOT and wait five years, or don't and regret it. There's tons of opportunity in both investment and development in the space.