It was having same issue when I used Piwik first time Piwik do not show statistics after installation though. Do you not see any of logging of the ip’s ? I am not personally using Matomo right now, but while packaging I saw you need to enable geoip module for nginx. Did you installed that module? I deliberately did not go deeper into fine tune it because I was expecting Matomo to work without the need to use this module and I thought this setting for advance users.
It would be good if can pin point the problem so that the package could be improved. In my opinion the problem would be some addition steps and maybe an additional dependency to be installed.