Not too far from my current interpretation. I think the teaser is mostly symbolism, which makes sense considering the game should be in the early stages of production.

I won't explain all the smaller details, but the main themes I recognized are:

• Reincarnation: we have an adult and a baby connected in a very Japanese way with a string, that could represent the "time" that connects them (they are the same entity) yet makes them different (he keeps cycling between adult and baby, alive and dead, longing to become each other).
• Samsara and memes (not a first time for Kojima): concepts close with reincarnation that add a lot to the teaser. We have a barren volcanic beach and dead animals, that could mean the food chain isn't connected anymore because oil killed all plants, which could explain the specific species found dead in the teaser. We have animals connected through strings which could represent their "life cycle"; they would usually rebecome the only thing they could be throughout their different forms (evolution): living beings that can't stay as static as the black beach that became their grave, but have to keep doing, living, eating each other, dying, living again (see "I'll keep coming" and the part of the Kojima interview about waves). Memes could be the cause the protagonist (Norman Reedus) always rebecomes himself, so we can play his multiple lifes without him changing too much (Ludens in armor being one of these).

With this in mind, the 5 characters at the end could be demiurges: they once created the world and, seeing it's dying on the plant/animal scale, they returned to put new life to it on the planetary scale, restarting the cycle of the planet.