Normal Xml and sql files that are loaded into the game via "UpdateDatabase" actions can have the same name in multiple different mods because the contents of these files is loaded into the game's database rather than the file itself as a "unit".
Xml files which are "context" files for UI will often have the same name across differing mods because they must in order for the game to accept them as the new version of the file to use for for example the Unit Panel. But these types of xml-files have the same conflict issues as lua files of the same name (especially for lua files that are replaceing standard game files for UI panels because the game can only ever have one version of the file at any one time).