Looks like the abyss just does whatever the ruling entity in it wants it to.
Sumeru had Marana spreading forbidden knowledge, Fontaine had the whale sucking up energy in the primordial sea, Natlan had gosoytoth waging war and going apeshit.
Hard to tell wtf is the deal with the abyss after the Skirk chapter, but one thing is sure. The abyss is not an entity and it doesn't act with a singular goal in mind like Celestia thought.
Another thing is weird, Skirk claims that the abyss is a natural part of the world order, but Voyager called it a calamity and Phanes has forbidden its research and development. Did phanes bring the abyss to Teyvat, did him losing his authority cause it to crash out?