That’s one way of looking at it. A reverse way is perhaps sleeping (and also as described in my above post, daytime standing, walking, and sitting) positions can reduce stressors.
Certainly, when one is physically exhausted, falling asleep is rapid. Why not, then, also mental exhaustion or agitation? Eastern mystics have always emphasized the role of meditation in relaxing the mind. How does sleep affect this?
The first and most critical step of meditation is to straighten the spine. When one sleeps, one can become bent in numerous ways, such that some muscles are overstretched and some understretched. A natural straightening of the spine will help these muscles to attain correct tone.
Stressors are usually compounded by out-of-tone muscles and glands. The reasons why takes some time to explain and will be skipped here. The general idea is to allows the stressors’ muscular and glandular compounding to be reduced by counteracting muscles, to achieve good muscular tonicity. With this, the degree of stress felt reduces rapidly.
Hence, proper sleeping position, in my opinion, is optimal on the back, such that the spine’s S shape is properly stretched, and then stretching other muscle groups during sleeping movements. Unfortunately, to get to this point, one may need to do lots of extra stretching work. Once one has sleeping illnesses, it takes some time and effort to recover.