16GB is plenty for a Plex home server.

Yes, 32GB is overkill for what you described. Plex itself barely touches RAM unless you’re doing weird stuff like in-memory transcoding, and you’re not. Docker containers—unless you’re running a dozen heavy databases or something—usually sit under 2GB total. File sharing is essentially free.

You’ll be fine with 8GB for that workload. I’d go 16GB just to have headroom for future containers, but 32GB is money you don’t need to spend. That extra cash is better spent on a better CPU for transcoding or more storage.

Save your money. You won’t notice the difference.