How would you comment on this: "A responsible employee is one who disagrees and says so?

A responsible employee is one who understands how their boss defines a responsible employee. Some bosses want and even encourage disagreement. Other boss want to be surrounded by yes men. The smart employee figures out what the boss wants and either does that or finds a new job.

A responsible employee is one who disagrees and says so when it is appropriate to do so and in a manner appropriate to their role.

That statement would not apply in most instances.