Discovered Plex Autoscan a few weeks ago and love it so far. As far as I know it's not containerized but I could be wrong, but you can install it on the host, it's a python based app and compatible with Plex docker. The setup can be a little daunting but when you get it setup properly it requires no care/feeding, and works great. Here's some of the benefits I've learned/leveraged:
No more Plex scans through tons of dirs for library updates, it monitors your gdrive for adds/removes/changes/deletes on your media folders, once detected it ensures the file is showing up in your mapped mounts, then notifies Plex to update that specific item in a targeted manner.
It keeps a DB of your items so it can see what is missing and have it added.
It can empty trash in Plex but can be configured to only do so if mount is mounted and/or if there's not more than x items in trash (so it doesn't empty mass items in the event of a config issue)
When you connect sonarr/radarr to it, it can fix incorrect matches in Plex to their correct matches.
So far it works great and is far more efficient for large libraries. For the record I have no affiliation with this project, just a fan and wanted to share.