Yes, Oracle is the most secure option for a database management system, but do all government databases need such a high level of security? Is the excessive cost of Oracle worth the extra security?
My agency mandates the use of Oracle (I believe this is mostly government-wide) in all database applications. This creates a huge and often unnecessary cost, particularly for non-critical databases that hold public information.
The details of Oracle vs MySQL vs any other DBMS don't need to be discussed here, but MySQL offers huge cost savings and is a perfectly good choice for many applications. Unfortunately, it's not an option to us.
The federal government has practically given Oracle (and Microsoft) a monopoly, so there is little motivation to cut prices. We need other options.