I agree, it seems the stealth effect only applies to the UI. Animals still see you, hear you, and react to you. I picked up the game again recently after taking a few months break, and in older version of both the game and trainer, I would walk around never triggering any warning call at all.Thank you for the update. I've tested the trainer and stealth activates again. The displays for visibility and sound don't move. Animals can still see you though and they also seem to hear you too.
The old stealth option made it possible to run around directly in front of animals and they won't bother.