I am also fascinated by the whole crypto/blockchain fad and my due diligence so far has led me to being very negative on this whole sector. In fact, I would favor regulating blockchain and crypto out of existence based on one single set of facts.
1 Visa transactions using conventional systems uses 0.001 kWh
1 Ethereum transaction using PoS blockchain uses 0.030 kWh
1 Bitcoin transaction using PoW blockchain uses 220,000,000 kWh
Even after the shift to PoS, ethereum is an order of magnitude less energy efficient than other non-blockchain databases. Crypto is an ecological disaster, at least until fusion power provides unlimited energy.
In addition, consider Visanet, the global non-blockchain network that controls Visa transactions. It averages about 2000 transactions/sec (tps) with a theoretical max of 65,000 tps. Compare this with current Bitcoin and ethereum transaction speeds of between 7-20 tps. Clearly not ready for primetime.
What this means is that blockchain is not scalable based on current technology, and even if it was scalable the energy waste would be enormous. The solution being pushed by advocates is blockchain sharding, a technology still in its infancy. By breaking the blockchain network into smaller “shards”, one can in theory greatly increase tps. The cost is a much more complex network that probably compromises security and transparency, and there is still the issue of it guzzling energy.
In summary, there is much uncertainty as to whether blockchain can actually do the things proponents claim, much depends on new technology that has yet to be tested. And in a world faced with the simultaneous challenges of increasing energy demand and Climate Change, the energy wastefulness of blockchain is a major negative.