don't think it's a bug.
When Proxy LiteSpeed, backend server only know it LiteSpeed Server IP
this is how proxy works --- not only litespeed, but all web server. the REMOTE_ADDR will show proxy's IP.
X_REAL_IP is not a standard header, it's defined and used by certain web server and web application, its purpose is to let the backend know the REMOTE_ADDR which the proxy see.
so in litespeed's case, the web app at the backend can parse the request header X_FORWARDED_FOR to know the "real IP" when reach the proxy.