It's not about "running as administrator" in the same way that not being a member of a unix group isn't about "running as root".
Windows has a specific local security policy about creating symlinks.
Instead of deploying nuclear weapons to kill a flea, run the local security policy applet and add your account name to the access control list for the creating symlinks policy, e.g. LOCALMACHINE\user. Then things like git and other programs that try to make symlinks will work correctly.