Gladiator Swarms have superior mass efficiency compared to Bomber Squadrons and even other swarms such as the Charger Swarm. This allows your carrier to deal the most damage to anything that comes in range.
Gladiator Swarms are both durable and speedy, making them unlikely to be taken down before opening fire and giving you more time to deal damage.
Their extremely long flight time pretty much guarantees that any lone ship that is unable to defend itself from squadrons will eventually be destroyed even if the swarms only have minimal health remaining.
Gladiator Swarms are outranged by Bomber Squadrons, allowing other carriers to kite you unless you push your carrier with other ships such as cutters.