While that may be true, too many people screw up their systems with the plugin and I don't have time to maintain the plugin. Docker is just a better fit.
Technically I totally agree. But I am not so well with nginx config files and the GUI helped me to get to my target. Could the nginx plugin be used to simply write the config file? Then the user could specify the path to nginx config files of nginx container bind mount -> not access to whole system.
Edit: The integration to certs was also nice given that Letsencrypt was easy to integrate / select. I really miss those two pluggis.