Hell yeah it does. When I'm suited and booted or dressed really preppy, I get stopped by people all the time. People have stopped me just to say hi, women have approached me, people want me to join their MLM, and I've even had people ask me if I was hiring, and I didn't even have a business...
If image wasn't so important, companies wouldn't spend millions a year on style consultants and there wouldn't be so many books on the subject.
Check out Alpha M on YouTube. He has millions of subscribers, and all he does is talk about men improving their image.
Also check out Kevin Samuels, he's a brotha and he has good info on the subject.
Good for your friend though, I don't think many brothas are in the field, and a lot of us brothas really need help with our image.