Putting torpedo tubes on an aircraft carrier would require the carrier to close to torpedo range, precisely where such a valuable ship should not be. Defensive guns capable of driving off destroyers could be useful, especially during a night approach. Heavy artillery intended for a surface duel made less sense. Interwar Royal Navy practice normally surrounded carriers with cruisers and destroyers that could handle those threats. The escort system therefore reduced the incentive to arm British carriers like surface combatants.
Notable Point · 1:42-2:39
Why British carriers relied on escorts instead of torpedoes
A short design aside explains why British carriers needed defensive guns and escorts, not ship-launched torpedo attacks.