Yeah, it's a little exposed, but not too bad. That's the price we pay to have a, AWD vehicle with both decent ground clearance and low floors and interior space. Packaging becomes more difficult without intruding into the cabin. It's a jacked-up car, not a 4Runner.
At least the rear diff has more protection than previous years. The exhaust is a wear/sacrificial item.
If anyone is touching rocks with the Subaru aluminium skidplate / splashguard available as an accessory for your Forester, not only are they putting the rest of the Forester at risk, they are putting the skidplate itself at risk. By no means is that part a "real" skidplate. Don't get me wrong, it is 1000 times better than the plastic one that comes on the vehicle, and I have one, but in no way could that thing withstand a real smash against some firmly planted rocks or roots. It is held on by four bolt which are not connected to the most solid framework and the side wing brackets connect to the vehicle with plastic clips.... if any of us are touching the front skid plate on rocks, the trail is such that the rest of the Forester is at great risk of damage.