Previous thread (featuring Ben Horowitz on 21.co): https://news.ycombinator.com/item?id=13485488
Two takeaways:
1. A response looks like this: https://monosnap.com/file/CbRNrj7TUUhaLolVTLYJhrPxUdsYOK
2. A16Z invested in 21.co when it still was a Bitcoin mining hardware startup: https://techcrunch.com/2015/05/18/what-is-21-co-really-doing...