Blue
Ravenous Bugblatter Beast of Traal
That'd be great. In theory.
In practice, you'd have missing CDs and WotC would continually be fielding complaints about absent discs.
And you'd *still* have people complaining about having to sign up to the DMsGuild.
And if no credit card is associated with the account you'd instantly have people make temporary burn accounts that could be banned, using the code, and then distributing the PDF.
To say nothing of people who don't have optical drives… How many college and university students might only have a smartphone or tablet? Will optical drives still be in heavy use in five years? Ten?
Sorry, I didn't explain well. Instead of a CD, it comes with a sealed unique identifier. On paper. Maybe something that looks like a steam or amazon gift card number, big enough space not to hit it typing randomly.
And sure, people can pirate it. They still will anyway so that's not a factor. But with legitimate PDFs out there they will at least be getting some cut of the people-who-want-PDFs market.