Can loss of nocturnal erections cause desensitation of penis making sex less pleasurable and harder to reach orgasm? can this condition be improved?

No and yes,: The loss of nocturnal erections can not cause desensitization or difficulty in reaching an orgasm. The fact that you have no nocturnal erections, however, may be a symptom of other endocrine or medical problems which decrease libido and sex drive. You need a consult and lab studies with your physician to rule out medical problems. Meds, diabetes, low T and other disorders can cause this. Good luck