> - /bin/python3 is a symlink to /usr/bin/python3 You don't symlink everything in /usr/bin to /bin, just "all regular files that have traditionally been in /b

> - /bin/python3 is a symlink to /usr/bin/python3 You don't symlink everything in /usr/bin to /bin, just "all regular files that have traditionally been in /bin" (per the article). python3 has not traditionally been in /bin, so /bin/python3 would not be linked.