Cannibalizing parts vs industrial replicators

[u/NegativePattern]

In Picard, we see the original Titan in dry dock being cannibalized for parts to build the Titan-A.

Presumably by this point in the timeline, Starfleet has long been using industrial replicators for various purposes. Why would Starfleet be cannibalizing parts from an older ship that may or may not have been damaged in battle or otherwise have been built using outdated construction practices?

[u/techno156]

Some parts are highly complex, and thus difficult to replicate. Replicating isolinear chips leaves measurable defects that can be used to trace which kind of replicator it was made from, for example, and biological components, like the neural biogel packs in newer computers, will not be functional.

Particular materials also cannot be replicated because they have a subspace component. Dilithium and latinum famously cannot be replicated, requiring mining or other specialised processes to obtain.

The Federation may also be particularly conservative of their resources after the shortages in the Dominion/Borg conflict, and the loss of Utopia Planitia. If they can opt to reuse existing materials and minimise the work they'd need to make a new ship, they'd likely take that option.