I am not experiencing gradient changes on kickr climb when not in erg mode during structured workouts. It works fine on non workouts. Is this expected? If so, why?!
The short answer appears to be that in workout mode, so that you can focus on hitting your power/cadence numbers without having to account for the additional variable of a changing slope, Zwift artificially “flattens” any course you happen to be on–i.e. even though a course may have significant inclined/declines, and even though you can see the % of the slope of screen, you’re essentially riding a flat road. As a result, your Kickr doesn’t tell the Climb to do anything.
See here, if you want more conversation about it.