I didn't ask a question. :-)

If you need more / different isolation, you're going to need custom nftables/ebtables rules.

In another model you could drop each bridge onto a unique vlan, and firewall them.

There's tons of options out there.

Anyway, if you had more specifics to go off of, there's plenty of network engineers and kubernetes/docker admins floating around willing to help - maybe start a Ask HN post?

You're still offering suggestions I said I didn't ask for. I'm sure you're trying to help, but at this point you're coming across as passive-aggressive.

You asked for the notes of somebody that's done isolation in different ways in docker.

Your responses have confused me so much I showed them to my partner, who is also confused.

I asked the person I was replying to for their notes because they were asking if anyone was interested in them.