[Squithrilve]

> while other solutions like proof of stake / space / ... exist and are much more energy efficient.

They are only proposed solutions, not implemented in any existing systems so it's not fair to compare them. Proof of stake for example has numerous drawbacks: https://en.wikipedia.org/wiki/Proof-of-stake#Criticism

[viraptor]

Filecoin did some good improvements in cpu/energy usage and PoSpace