Chia Network explains the reason for the prefarm and how it’s going to be used in their whitepaper https://www.chia.net/assets/Chia-Business-Whitepaper-2022-02...

Also worth checking about Chia Network projects with WorldBank and InternationalFinanceCorporation for carbon credits market https://www.chia.net/2022/08/17/bringing-transparency-and-ef... about some real use that is launching very soon.

In the beginning everyone had to run a full node even if they weren’t farming (in Chia instead of mining it’s 2 stages, first plotting and then farming) but earlier this year Chia released a new light wallet which doesn’t run a full node. Now it should be mostly actual farmers that run full nodes. Chia currently has 22 EiB of netspace which would be more than 1.5 million of 14 TB hard drives.

They made a pooling protocol too to avoid the issue bitcoin had with centralization of the big pools.

So is this 120k nodes are validating/producing/verifying the blocks?