The poster is sharing how @dollarvigilante made $15,000+ on his first post.
The secret to his success is that he already had a following of thousands of cryptocurrency enthusiasts including the founders of Steemit. The same poster now makes $30 - $150 per post, which is much more than "average", and this is based on continuously posting original and interesting content.
Overnight success on Steemit is VERY RARE. To get rich with Steemit, most people will have to work hard to build a following and produce content that your following will upvote.
The best way to earn money on Steemit is to be involved. Talk about things you're interested in and reply to posts that interest you in a way that creates conversations.