Yeah this is mostly deliberate. The value returned is an integer which is provided by the mysqli connection from a property called server_version
.
Either MariaDB is reporting that as its version, or it's inferring it from the version string which is invariably made up of the equivalent MySQL version and the actual MariaDB version.
We only need to know what the equivalent MySQL version is, anyway. This is the same value we use, say, when you're upgrading to XF 2.0 to make sure you're using at least MySQL 5.5.0.
This is the second bug report about this new information block. Really, this information is just a "best effort" collection of stuff that may or may not be useful if you're ever troubleshooting an issue. If it's there, wonderful. If it's not, it doesn't matter.