Accutane user here who went on ~1.5 courses before stopping cold turkey ~6 years ago. Exact same symptoms as PFS btw.
I’ve only had two instances where I felt like I was cured completely.
First instance: took antibiotics for a wisdom teeth extraction. About ~12 hours later I had a rock solid erection comparable to my former self as well as the libido (and this is with extreme pain and shock from my teeth extraction pain!). The effects seemed to last for about two weeks. The tapering off coincided with me partying fairly hard that weekend with bad food and alcohol.
Second instance: second day of carnivore diet. I had been miserable all day and all of a sudden I felt a return to normal. My erection quality was maybe 90-95%? I continued my strict carnivore diet for 3 additional weeks but I lost this effect by the third day. Interestingly, I was able to sustain maybe ~70% return to baseline with high libido and a relatively good erection for about 1 week AFTER ending my carnivore diet and returning to a low carb diet but not during my diet.
day 1 of carnivore - no change
day 2 - 95%
day 3 - 50%
days 4-21 - 0% again
end carnivore diet
days 1-7 - ~70%
These instances lead me to think that we can at least partly recover from PFS/PAS by resolving some underlying gut microbiome issues. Others have also reported some temporary relief with antibiotics as well on this forum. My understanding of this is also due to the fact that accutane users suffer later in life from gut issues like Crohn’s disease as well.