Werebear Form’s Rampage is often interrupted during or shortly after significant changes in elevation even if the key remains pressed.
I recorded an example - the button for Rampage remains held down until the very end, where I hit a wall and stop as expected, but Rampage abruptly stops both halfway down the staircase and near the bottom, without bumping into any terrain. I should emphasize that this is just one example - this has been happening on many (maybe even most) slopes throughout the game, going up or down.