Keychain keeps things simple for keeping passwords together and was a handy fallback if I forgot something. And while the format is no good off the Mac, when I would upgrade, the file was able to be used once copied into the right place.
But there is no support for exporting and hardly any documentation. My passwords are mine, thank you.
Migration Score
AWFUL
Migration Options
Good Luck
While I believe the idea behind Keychain is sound, that's not the way GNOME works.
After much searching, I was able to export my passwords from Keychain.