Lane assist has direction arrow for a lane and no route is required. It's a driving aid. Example, street has 3 lanes which would be straight until at intersection which far left is for left* turn, middle for straight and far right for right* turn.

Junction view has possible exit directions to take. Usually the one you need to take is not dimmed. It's a direction aid and require a route to show. Not all junction view are available for an exit.

You can google the image/snap to see the difference.


* They could go straight as well