As for why Dubas would even bother talking about Ceci: it was a specific question brought up by a reporter that wasn't Simmons.
Treating former players respectfully is just good HR and PR. Dubas' words and actions are constantly evaluated, not just by us, but by his current players and future players to come. They see a manager who tries to use every resource to position his players to succeed, treats them fairly in negotiation, and emphasizes their positives in public. This costs Dubas almost nothing, but is valuable down the road when a vet or rebounding player is looking for a place to rebuild on a show-me deal.
Compare and contrast to Vegas who have pivoted from plucky castoffs who work harder together to a ruthless mercenary outfit because a couple of really sexy players came within reach.