At the end the author makes the conclusion that this "sexy change" was sub-optimal but the problem was a copywriting issue. A large red button that says Buy It?

At the end the author makes the conclusion that this "sexy change" was sub-optimal but the problem was a copywriting issue. A large red button that says Buy It? How could anyone not guess that wouldn't get clicked much. People don't want to immediately buy something without reading about it first, especially when coming from an email. Also: why a huge red button instead of green or any other color? Red has many negative connotations (and is also used to signify the end of a process) so it was probably the worst possible color choice. I bet if it said See It and was green or blue the CTR would've eclipsed the unstyled email very easily. The problem wasn't going from an unsexy email to a sexy one, it was the boneheaded copywriting errors and color choices. He should find a new designer.