It seems the use of aromatase inhibitors in women lead to altered gene expression in vaginal biopsies which lead to vaginal atrophy. Similarly, PFS were shown to have altered genes in penile biopsies.
Another pubmed article below shows the negative effects of aromatase inhibition in women leading to vaginal atrophy.
It seems altering the human endocrine system through either 5 alpha reductase inhibition (blocking DHT) and aromatase inhibition (estrogen inhibition) is not always a free lunch and can lead to catastrophic sexual issues.
This has even been seen anecdotally (and in this forum) of male bodybuilders using AIs and getting “Post AI Syndrome” which has very similar if not identical symptoms to PFS (anhedonia, ED, genital numbness, etc.)
This was unfortunately seen on here when @douglasmich used an AI on top of Saw P induced PFS which sadly lead to his suicide.