Why would the legs on a radial through hole inductor be different lengths from eash other? There is no polarity to indicate like a LED or Electrolytic cap...
Sometimes the properties are a bit different depending on mounting direction. From the murata website (https://www.murata.com/en-us/products/emiconfun/inductor/2012/05/14/en-20120514-p1):
If the inductor structure is not perfectly symmetric, properties will change with the mounting direction. We therefore leave a mark so that the user will know the inductor has directionality. That way, when they use the inductor, they can hope to make the fullest use of the intended properties.
Also it can be useful to know the polarity to understand the direction of the magnetic field that will be induced. If a lot of inductors are used close to each other, their fields will interact.