Black Hat hacker claims he can make $15k to $20k an hour

Making $15k-$20k "in an hour" is not the same as making it "an hour" (equivalent to per hour). This is a mistake often made in evaluating the profitability of a business ideas. For example, our business runs procurement events that culminate in a real-time reverse auction with a specified duration of around 15 minutes. It is not unusual for us to bill $40k for a large event. But what about all the work we do that leads up to that brief event? We can't rationally exclude that in the evaluation of our profitability

Likewise with this blackhat; how long did it take to build their botnet? How many $15k-$20k opportunities present themselves in a year? How much of that figure can be attributed to self-agrandisement; an attribute commonly associated with l33t hackers?

Spamming and DDoS...pfft...too much work.

I would have just written a blog post on chrome passwords.

Right. I say I can make $100k an hour.

Can and does are two very different things.