This is probably due to concern about legal regulations around temporarily recording someone else's voice so it can be processed for translation. After all, there is no mechanism for the person you're talking to to provide "consent", and the EU does have particularly strong laws on this.
Alternatively it might have something to do with the translation being performed in iOS, and the capability not being exposed to competitor audio devices, and therefore Apple needs assurance the EU won't consider it anticompetitive?
Alternatively it might have something to do with the translation being performed in iOS, and the capability not being exposed to competitor audio devices, and therefore Apple needs assurance the EU won't consider it anticompetitive?
Or both.