I didn't find it helpful. It boils down to having something to sell, then messaging a lot of people, the messaging more, then more. Before opening the PDF I kind of thought there were some more insight. Half the screenshots are email, not Twitter DMs.
Ah, the title is 'Guide to Cold Emails and DMs", so the confusing part was the HackerNews submission title.
Lessons are applicable to both.
But like a good DM, needed a good Hacker News title!
Recommend you read through again.
I think you're missing the main learnings.
But will take this feedback into consideration for the next PDF I make.