Thank you for your reply Judy.
As explained: it seems that those steps are not full proof: M1 MacMini with latest macOS, iPad Pro 2020 latest iPadOS:
it you get ‘connecting to library’ - a restart of Mac and iPad does not resolve it nor reinstalling the remote app
only enable home sharing resolves this.
however the iTunes remote app is limited in functionality as I would like to use the new Hi Res formats available through Apple Music and play back on my HiFi setup with audiophile DAC attached to the MacMini.
iTunes remote only allows access to locally stored music on the Mac.
I hope this gets resolved soon as I now need to resort to a VNC connection from my iPad to manage the Music app on my Mac.