So why is the film called Johnny Mnemonic? It makes it seem like that's his name, but at no point is he called anything other than just Johnny. Its not even a nickname or anything like that.
Anyway, I think it is fascinating how he has no redeeming qualities. He just cares about money and hookers, and not all the people dying. He constantly tries to give the data to the bad guys, and even at the end he's only helping the good guys since they are the only ones who will take the data out without killing him. He's not even good at his job. If he were really such a professional, the instant he heard that it would be too much data, he would just leave and drop the job.