I can't believe there are people defending this.
If Sony had decided back when he made an account that it wasn't an acceptable name and asked him to change it, it would still be bullshit, but it wouldn't be so bad.
If Sony had stood by their initial offer of just changing his screen name, or if that's impossible because of how their database is set up, offered to transfer all his purchases to a new account, then it wouldn't be so bad.
But as it stands, they are stealing thousands of dollars in purchases from this guy just because they decided they didn't like his name ten years after the fact. And that's unforgivable. You can't just take thousands of dollars in purchases away from someone on a whim like that. Imagine if you bought a TV, and then a few years later, someone stormed into your house and took the TV back without reimbursing you because they decided they didn't like the name on your credit card. That's exactly what's happening here. It would be illegal for this to happen with real, physical goods, so it should also be illegal for it to happen with digital goods.