The embedded seems to ignore that most modern systems are distributed now and an operation will spawn multiple services. So an external system is better for that usecase I would say.
Where is the state stored? What if I have 5 copies of my service now, and 3 later. What happens to the "embedded state"? Was it on the container? Did it just evaporate? Was it on a volume? Is it stuck in limbo? Even if it was put into s3 it would be stuck in limbo.
DBOS solves this problem by storing state in Postgres, which is really good at coordinating multiple copies of the same service. Essentially, Postgres does the hard parts of external orchestration, letting you work with a simple library abstraction.