Was that by design so that Montana could shoot sentries from the safety of the walled ledge or did Gearbox not look at the whole map?
If the enemy team is occupying YOUR sniper perch, you’ve already messed up on the lane push.
This isn’t an issue if your team is properly pushing back. Not like you couldn’t get up on the ledge by running around the corner to the stairs anyway prior to the patch changes.
You also have a Thumper cannon that should be upgraded that is in direct LOS of that perch to help you push people off it.