It opens with irony while still addressing the reader. For "normal" subscribers of "normal" newsletters, something like this wouldn't land. But for designers, written by designers, it's like an inside joke. This builds immediate rapport while grabbing attention and leading into the next section.

Humor is vastly under-utilized in marketing. This is a wonderful twist to the obligatory "Thanks for subscribing." Stay away from anything bland, default, or that could be copy-pasted into any other newsletter's email and still work.

Can't forget about the true meaning of the email: To deliver the resource requested. Splitting it out into a bullet point and highlighting in red makes it easy to identify and understand that it's a link. They even sneak in a coupon code for anyone who needs a nudge to purchase.

I love that it circles back with a paragraph that answer's "Is this for people like me?" and "What should I expect?" Don't forget to set subscribers' expectations and give them an idea of what's to come. It also helps to reaffirm who the newsletter is for so they can self-identify, which will keep the right subscribers around and help the wrong subscribers self-select themselves out.

The email concludes with a large button that repeats the main call to action, which is the original purpose of the email: The free resource. Repeating calls to action in a consistent fashion helps reaffirm the reader's understanding of what you want them to do and increase the likelihood they'll click through.