System Information
Operating system: Windows-10-10.0.19041-SP0 64 Bits
Graphics card: Quadro M4000M/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 452.06
Blender Version
Broken: version: 2.91.0 Alpha, branch: master, commit date: 2020-09-18 08:39, hash: rB940ef1a4e862
Worked: (newest version of Blender that worked as expected)
Short description of error
Autokey only inserts keys to the fcruve it doesn't change the values when pasting a pose into an action layer over a CLIP in the NLA
Exact steps for others to reproduce the error
Create an armature.
Animate the bone.
Push it to a clip in the NLA
Keyframe into the empty action say frame 1 and 30 with diffrent values.
Copy the pose from frame 1 and paste it anywhere between 1-30 with auto key on.
Notice in the graph editor that the keys are inserted to the existing curves but nothing changes.
Now hit I to insert a keyframe and you will see that the curve and keys values are correctly evaluated.

