So why was Summoner advertised as a pet class
The only viable pet is the one that acts as DoT buff, Titan has absolutely no role in party content and Ifrit is strictly inferior to Garuda in every encounter. Even if they were to add more Egis the only differential between them would be DPS (Or lack there-of) meaning you'll still only ever make use of one pet in any encounter. What's the point of utility if DPS is always the better option and what utility the other Egis do offer is already covered by another role?