Aside from one (seemingly very out of place at the time) early mention that the author used Bitcoin, there was no hint of it being pro-bitcoin until the very, very end.

I found it to be a very worthwhile article right up until that point and even slightly intriguing from an academic perspective after that point.

I despise the endless blind parroting of the typical cryptobro refrains elsewhere on the Internet when crypto is brought up and I still liked the article, so I wouldn't write it off just because one guy with a cryptohammer inevitably sees the very real SMTP problem as a cryptonail in the end. It's natural when you have a "solution in search of a problem" situation like we do with crypto (and block chain, and for that matter SharePoint. People with knowledge of a thing often try to use it to solve problems it probably wasn't meant for.)