I will be going down this road really soon as I asked about the lack of updates to linuxserver's tvheadend and they said
No one within the team actively uses this container anymore. Seems like it's been attempting to build but had errors for some reason when pushing the built images.
Aside to this, due to my comment above, we are discussing internally what to do with this container so it might be wise to jump over to tvheadends official offering for something that's more up to date.
Anyone played with the official container in rootless podman? Might be time for me to try that.