In my opinion, S2 is the correct classification. The trail has some very steep sections. Even if it is dry, braking must be measured. There are also a few - but steep and high - rock steps. It's not really narrow - but it's partially washed deep into the ground.
At the end, the many water-repellent stone obstacles are “annoying”. You must not underestimate these high, steep obstacles - otherwise the snake will strike in the jacket or hose!