a16z: Based on our analysis using many of the approaches described above, we estimate there are 30–60 million real monthly crypto users today. It’s also just 5–10% of the 617 million global crypto owners reported by Cryptocom in June. This differential suggests there is a huge opportunity to convert existing crypto owners — who are mostly passive holders

https://a16zcrypto.com/posts/article/estimating-crypto-users/