The problem is in the UI (User Interface) of your blender file, open a new general file, click file > open > don’t save the general file > after choosing the file you want, click the gear icon (top right), it opens a window , uncheck (Load UI). And now if you create Armature you will see it.
You saved the day! Thanks!!
Leaving this here cause this was the first result in google. You can just go back into pose mode and press A for select all and alt h and it’ll come back. Might not have been that way when this was first posted but it works that way now at least.