We are not aware of any problems regarding MacOS Sierra updates.
I think it's unlikely that a broken animation stems from an OS update.
Can you send us the fbx file (either attached here or to an email to email@example.com), so that we can investigate the animation problem?
almost 5 years ago
I upgraded my operating system to Sierra 10.12.1 and FBX 3D models that worked before the upgrade stopped working. When I open with Encoder feature a distortion in the animation that did not exist before.
What can I do to resolve this since the FBX Reviewer this problem did not happen, that is, the FBX still works the same as before the system upgrade?