There's nothing to install on a Mac to get an sftp server running- it's already there when enabling "Remote Login" in the Sharing System Preferences. Configuring a Docker instance just to get access to files is a laughably complex solution to something that already works and is built into the OS.No, it is not. It is not a joke.
If this talk is about sFTP server running on a Mac so Dockerization could provide it easily: Docker container with mounted volumes. Just I see there a lot of user complains sFTP (server?!) is very hard to install on Mac now: so, Docker might be an option then.