iTunes was long able to create an XML file, which was a readable dump of its library file, so the apps could access information about your library. This file was also useful to have as a backup; if your iTunes Library file got corrupted, loading the XML file could allow you to recover your library.
In the macOS Catalina Music app, you can no longer have this file created automatically, but you can create it manually. This can be useful if you’re a DJ and want to use it with software that hasn’t been updated to use the iTunesLibrary framework, or if you just want to have a backup of your library.
To do this, choose File > Library > Export Library, name the file, and save it.
Again, there’s no way to automate this, but if you do need the file to use with a DJ app, you can just dump it before your set.
Learn more about the new media apps that replace iTunes in macOS Catalina in my new book, Take Control of macOS Media Apps.