ArcGIS Pro 3.4.2
I don’t make formal maps with legends very often, but it seems to me it would be more useful for the raster value, such as elevation, be used as the default legend label, instead of the color bit number as the legend label.

I could be missing something. I’m not a cartographer.
How to symbolize & label Lidar raster layer in legend? What is 0-255?