Crypto and blockchain marketing has evolved from a niche interest to a mainstream industry, according to Amanda Cassatt, founder and CEO of Web3 marketing company Serotonin. Speaking at Proof of Talk in Paris, Cassatt shared her journey from discovering Ethereum in 2015 to building a successful marketing empire. She highlighted the challenges of marketing in the early days of crypto, when words like Bitcoin or Ethereum were banned on major platforms. Cassatt also emphasized the importance of building organic communities and treating every startup as its own niche media company.