It would be very useful to rotate text objects for example 60 degrees.
The stepsize of 90 is too high. A stepsize of 1 degree should work for the most situations.
So you can add a watermark f.e. “copy” over the hole page without using an image with the rotated text.
For simple text objects, try to use a negative value like -60
However, this will not work well with object linking, also, the object’s frame is not the reference anymore as you can see from the screenshot. Not all export formats work with free rotation. This is why we never documented this hidden feature.