You have to remove our comment out the assets location block. It may be possible to just exclude uploads, but you'll need to research the nginx syntax for that yourself.
It is actually planned: https://github.com/NodeBB/NodeBB/issues/5736
Two of the permissions that are supposed to be split are Global account info access and
Global user sessions access.
Unfortunately, there seems to be no ETA, and the issue is from 2017, so it might take some time before it's added... But there is hope 🙂
I can confirm that the "Access Topics" privilege is not functioning correctly, so will need to look into that.
However, with "Create Topics" disabled, the "New Topic" button is not present, and the category itself is not present in the composer dropdown, so that privilege is working as intended.