We often label with numbers in AGOL. In cases like these it would make sense for the labels to have no rotation and just be horizontal instead of following the rotation of the lines. This is especially true since 6's and 9's look the same on lines oriented up and down, like in the image below.

Although a workaround could be to publish a point layer for labels, I don't want the public to see that as a separate layer, and if I have it hidden the labels would remain after hiding the lines... it's also just annoying to have to set up every time.
A native way in AGOL to remove rotations in labels would make maps like these neater and more legible.