Gary, I think if MS open-sourced the MCM questions and scenarios, you'd fairly quickly find people using them as templates to create new questions and scenarios for newer versions of SQL.
Therein lies the problem. What's to stop someone forking it with good old favourites like;
Q. "What do you do when your database is in suspect mode?"
A. "Detatch the database, delete the log file, reattatch the database. Everything will be fine"
A. "Run dbcc checkdb repair allow data loss. What could possibly go wrong"
all with a shiny OpenMCM <Insert animal logo here> badge. There'd need to be some form of quality control in there, and I can't see MS taking that on board
I'm a DBA.
I'm not paid to solve problems. I'm paid to prevent them.