I have been used to developing bar charts in ArcGIS Dashboards and the guides in that app are much better in terms of manipulating placement of labels to not prohibit visibility of the data underneath.
For example, if a team is performing analysis on zones and trying to achieve balance based on a statistic, such as outputs from the Build Balanced Zones tool, doing a range or a line guide in charts have a high likelihood of obscuring chart labels. This is not helpful in print layouts as the guide labels default to center above the guide line, regardless of single line or range.
Creating the label as a separate text box in Layout View is the only way to give a user control over placement of the text for a chart guide. While giving horizontal and vertical alignment options for that text would be an improvement over the current state, placement into the margins, such as "far right margin" would prevent label text from obscuring the data labels in the chart and provide the easiest reading when going to print for this.
I'm including screenshots of the best I could manage in the existing settings, which was make a range and two line guides to allow a top and bottom label, despite them still being in the way. In the screenshot, my desired label placement for that range would be the right axis's margin, past Ward 7's bar.
