I got my vero 4k+ for single use case to server as a plex client, and I have been very disappointed that there are no updates for 2 years for plex for kodi addon, no new plex features available etc.
Is there any initiative from osmc side to change that, contributing to plex for kodi project for example?
p.s. yes I have tried plex connect I did not like it one bit.
Unfortunately, no.
OSMC has nothing to do with the people who develop the Plex add-ons for Kodi. A majority of Kodi add-ons are created and maintained by third parties.
The current version of Plex for Kodi which is found in the official repo is 0.2.0 and I think that was released this year. There was a period of time where the client was being maintained by a third party and that has since stopped and it was switched back to Plex. If you had grabbed the add-on before I think you would probably need to remove that repro, delete the old Plex add-on (I think it stopped at v0.1.6), then install it again but this time directly from the Kodi repo.
I think the official Plex add-on is maintained by Plex themselves; so questions would be best directed to them.