Why an aviation support ship would also need a carrier role

Would a modern forward aviation support ship also need to act as a fleet carrier?

Yes, because a navy is unlikely to receive funding for separate maintenance and fleet-carrier ships.

A dedicated forward aviation maintenance ship would compete for money with an operational carrier. The panel does not expect a navy to secure funding for both specialized hulls. A modern support ship would therefore need enough aviation capability to serve as a fleet carrier as well. That dual role is driven by procurement reality rather than by the ideal arrangement for either mission. The short answer exposes how budget limits shape naval architecture before detailed design begins.