In Excel, you have the option of deciding what a Data Label shows, such as the series, category, or value. In Power BI Line Chart it only allows you to display the value. Please add in more granular ...
It doesn't seem reasonable that this is something available in Excel but not Power BI (and a feature I could use in Tableau when I last accessed it 4 years ago). Legend is of limited use for accessibility reasons e.g. the colour-blind. Ideally you would be able to label the beginning or end of a line, as labelling every mark on a line is cluttered. The tooltip doesn't serve as it gives you all values instead of just the value you're looking at and again these are largely distinguished by colour coding which again is limited use to the colour-blind.
