Not practically, except when it is a single-statement transaction.
Where deadlock prevention becomes useful/necessary is single UPDATE/DELETE statements that span across multiple nodes. When those are executed in parallel they could deadlock against each other due to non-deterministic execution order.
Citus currently uses predicate locks to avoid these deadlocks, but there's probably some room for improvement there. On the other hand, for Citus use cases UPDATE and DELETE across shards are mainly batch operations (e.g., delete old data), so there's not a strong need for it yet.
Where deadlock prevention becomes useful/necessary is single UPDATE/DELETE statements that span across multiple nodes. When those are executed in parallel they could deadlock against each other due to non-deterministic execution order.
Citus currently uses predicate locks to avoid these deadlocks, but there's probably some room for improvement there. On the other hand, for Citus use cases UPDATE and DELETE across shards are mainly batch operations (e.g., delete old data), so there's not a strong need for it yet.