Late gun destroyers provided cover while guided missiles matured. The Type 31 is offered as a contemporary parallel: its guns could put substantial defensive fire into the air against numerous drones. In the video's assessment, lasers are the expected next system but are not yet ready to replace that role. A transitional ship therefore needs weapons that can meet the threat during the wait.
Notable Point · 58:55-59:42
Gun armament covers the wait for new defensive weapons
The transition from guns to missiles supplies a comparison for Type 31 gun defence while laser weapons mature.