PoolVectorArrays were a thing in 3.x it seems
https://docs.godotengine.org/en/stable/classes/class_poolvector2array.html?highlight=poolvector2array

They don't exist in 4.x https://docs.godotengine.org/en/latest/classes/class_poolvector2array.html?highlight=poolvector2array
PackedVectorXArrays replaced them.

Yet, in the docs, there is still a location they are referenced:
https://docs.godotengine.org/en/latest/development/cpp/core_types.html?highlight=poolvector#allocating-memory
pool_vector.h especially is a dead link and has been long deleted. memory.h seems to have completely remade it to use MemoryStaticPool (can't confirm as I can't read the source code)

Related:

• Convert all references and instances of PoolVector to Vector godot#36311
• Every tutorials that refers to PoolVector (C++) or Pool*Array (scripting) should be reviewed for 4.0 #3192

My suggestions to close this and the above issue:

• Make https://docs.godotengine.org/en/latest/classes/class_poolvector2array.html?highlight=poolvector2array redirect to https://docs.godotengine.org/en/latest/classes/class_packedvector2array.html?highlight=packedvector2array
  Same applies for Vector3 and whatever converted from pool -> packed

• Update the https://docs.godotengine.org/en/latest/development/cpp/core_types.html?highlight=poolvector#allocating-memory with whatever is the new memory return/format