Let's put it this way. Dependent origination is the noble Right View.
The noble Right View of dependent origination leads to liberation.
The wrong views of eternalism and annihilationism lead to suffering.
The Buddha was only concerned with soteriology and he did not teach metaphysics or ontology. Physics is not his concern.
“Sir, they speak of this thing called ‘right view’. How is right view
defined?”
“Kaccāna, this world mostly relies on the dual notions of existence
and non-existence.
But when you truly see the origin of the world with right
understanding, you won’t have the notion of non-existence regarding
the world. And when you truly see the cessation of the world with
right understanding, you won’t have the notion of existence regarding
the world.
The world is for the most part shackled by attraction, grasping, and
insisting.
But if—when it comes to this attraction, grasping, mental fixation,
insistence, and underlying tendency—you don’t get attracted, grasp,
and commit to the notion ‘my self’, you’ll have no doubt or
uncertainty that what arises is just suffering arising, and what
ceases is just suffering ceasing. Your knowledge about this is
independent of others.
This is how right view is defined.
‘All exists’: this is one extreme.
‘All doesn’t exist’: this is the second extreme.
Avoiding these two extremes, the Realized One teaches by the middle
way:
‘Ignorance is a condition for choices. Choices are a condition for
consciousness. … That is how this entire mass of suffering originates.
When ignorance fades away and ceases with nothing left over, choices
cease. When choices cease, consciousness ceases. … That is how this
entire mass of suffering ceases.’”
SN 12.15
Thoughts about whether "I existed in the past" or "will I exist in the future" will lead to suffering. Dependent origination, when realized by the noble disciple, will lead to liberation.
When a noble disciple has clearly seen with right wisdom this
dependent origination and these dependently originated phenomena as
they are, it’s impossible for them to turn back to the past, thinking:
‘Did I exist in the past? Did I not exist in the past? What was I in
the past? How was I in the past? After being what, what did I become
in the past?’ Or to turn forward to the future, thinking: ‘Will I
exist in the future? Will I not exist in the future? What will I be in
the future? How will I be in the future? After being what, what will I
become in the future?’ Or to be undecided about the present, thinking:
‘Am I? Am I not? What am I? How am I? This sentient being—where did it
come from? And where will it go?’ Why is that? Because that noble
disciple has clearly seen with right wisdom this dependent origination
and these dependently originated phenomena as they are.”
SN 12.20
Also, as seen in SN 12.4-10, past Buddhas all rediscovered the same dependent origination on their own. So it's not skillful means (upaya) but it is a law of nature.