Jumping in to second immich-go, just used it recently. I had no issues other than Google Photos not giving me the data for shared albums (most of mine), which seems to be a Google Takeout issue.
To answer my own Q, yes, anything shared by others with you isn't in the takeout backup. You have to go to each such album and do Download All. Then you can import it with immich-go with the correct album name. If you already have that album, it will just add the missing content to it.