In The Hate U Give, when Khalil says “I been busy,” what does he mean?

Angie Thomas's The Hate U Give is at its most powerful when it is being its most real. This line comes up as a response from Khalil when Starr sees him at the party near the beginning of the book. As they reconnect, Khalil mentions that he hasn't heard from Starr in a long time. She mentions what has been keeping her busy, but then says "You're the one nobody sees anymore." Thomas then describes Khalil's response:

His dimples disappear. He wipes his nose like he always does before a lie. "I been busy."
Obviously. The brand-new Jordans, the crisp white tee, the diamonds in his ears. When you grow up in Garden Heights, you know what "busy" really means. (12)

Starr's observations reveal her understanding of what Khalil is really saying. He has been busy, but it's in a way that he doesn't want to admit. He is ashamed of what has been keeping him "busy." Thomas chooses to have Starr focus on the expensive articles of clothing that Khalil is wearing because she wants the reader to understand the subtext of "busy." Starr gets upset because she knows that in this situation, "busy" means that Khalil has been selling drugs. This is a point that comes up after he is killed by police, as some people write him off as just another drug dealer whose own choices got him killed. However, Starr comes to understand that Khalil's situation is far more complicated than the media makes it out to be.