I’m sorry, I think I gave you bad information. I have my containers set to unprivileged=no. I forgot about the “double negative” in how that flag was described.
So apparently my containers are privileged, so I don’t think I’ve ever tried to do what you are doing.
I believe you’re correct. I didn’t realize that I had my containers set to privileged. That would explain why I’ve never had issues with mounting shares.