What is Farcaster, and why did it raise 150M USD?

I take a deep dive into crypto-based social network Farcaster, aka Torment-Nexus-on-the-blockchain.

I think that crypto/web3 is mostly really dumb and bad, but I also do think that what happens on other decentralised social networks is relevant to understand the fediverse. The different protocols influence each other and I dont think they should be understood in isolation. That is why I wanted to have a better understanding of what Farcaster is, and why a16z wanted to spend so much money on it.