Different programs have different defaults.
But in your situation which would be more helpful - prevent this one docker command from using ipv6 (likely more difficult), or preventing all commands from using your broken ipv6 config (likely easier)?
I have no idea about the first. Maybe some people know this detail. But I'm sure that with a distro and version that you're running, there are lots of people who could help with the second. Raspberry Pi 3B+ is the hardware. What software are you using?