As told by Polygon, recursive zero-knowledge proofs were largely theoretical in 2014. By 2019, it took about 120 seconds to generate them. In 2020, that number fell to 60 seconds. This year, Plonky2 is set to allow such proofs to be generated in just 0.17 seconds. The network's developers allege that it is 100x faster than existing alternatives.
Such a class of algorithms could potentially enable horizontal or linear scaling of blockchains in the future. Nodes do not need to store the history of the blockchain's transactions to be up and running, thereby increasing the network's capacity with each one added. https://cointelegraph.com/news/zero-knowledge-scaling-tech-plonky-goes-live-on-polygon
