Obsolute pms settings - Custom URLs, whats the point?

@Suspense said:
Why is plex forcing a connection attempt on port 32400, when you specifically configure plex not to?.

That is not what the setting does.
It allows you to specify an additional, alternate URL for Plex clients to try and use. Just in case the direct connection (per local/private IP and port 32400) is not usable.
Nowhere does it say that other routes to contact the server are switched off by this.