[wellboy]

That's why Bitcoin has just implemented the Lightning Network and Ethereum is implementing Sharding and Plasma. Lightning is projected to be able to maintain 50,000 TPS in practice and billions of TPS in theory.

Furthermore, PoS systems such as Nano and IOTA aren't really more centralized than PoW systems such as Bitcoin and Ethereum, since only 6 entities possess more than 51% of the hashing power in Bitcoin. That's definitely more centralized than Nano or IOTA.

That's also the reason why Ethereum is moving to a PoS/PoW hybrid.

In a nutshell, near instant transactions with very high scalability and a very high degree of decentralization are already here(Bitcoin, Nano, IOTA). However, these technologies have not yet proven themselves and need to show their resilience against black swan events and hacks of all kinds.

We will see the results within the next year.