Idk if rsync traverses symlinks and filesystems by default,

From the man page:

Beginning with rsync 3.0.0, rsync always sends these implied directories as real directories in the file list, even if a path element is really a symlink on the sending side. This prevents some really unexpected behaviors when copying the full path of a file that you didn’t realize had a symlink in its path.

That means, if you’re transferring the file ~/foo/bar/file.txt, where ~/foo/bar/ is a symlink to ~/foo/baz, the baz directory will essentially be duplicated and end up as the real directory /SSD/foo/bar and /SSD/foo/baz.