Unfortunately we don't have any near term plans to support files/folders starting with '.' characters. I am discussing with relevant teams and if there is a feasibility, we will add it to our product roadmap.
To be honist i 'still' do not see why there is a restriction on any file or folder uploaded to the cloud. This seems pointless. Other cloud provideds do not have any restriction on file or folder types.
Please remove this restriction as soon as possible!