The option "connectTimeout" doesn't default on DriverManager.getLoginTimeout() as defined in JDBC spec : https://docs.oracle.com/javase/9/docs/api/java/sql/DriverManager.html#getLoginTimeout--

public static void setLoginTimeout(int seconds) : 

Sets the maximum time in seconds that a driver will wait while attempting to connect to a database once the driver has been identified.

The connector has an option "connectTimeout" that defaults to 30s when not set.
default must take DriverManager.getLoginTimeout() value if defined, or 30s if not.