As you probably realise, OpenVPN is Free Open Source Software
and the developers are hard working, dedicated and knowledgeable volunteers.
For those developers, the integration of OpenVPN and systemd has focused on the changes
required within OpenVPN to work reliably with systemd and utilising systemd's security advantages.
Currently, due to the major release of OpenVPN 2.4 and OpenSSL 1.1, the developers have had
a considerable work load.
You are welcome to join the developer team if you have some time and skills to offer.
(You can find details on the
OpenVPN wiki)
Hope that helps.