Sounds like my issue, my labs were really good , I strength train 3x week , low body fat etc..
I would suggest going to a Urologist and having a Doppler test done. Sounds like venous leakage, which is hereditary and gets worse over time.
I had great results with PDE5 inhibitors for 5-7 years, but the hardness started to slip . I went to higher dosages, then I had to do both Cialis and Viagra. Finally, my wood was not real hard no matter what. I went to Bi-Mix , but did not want to keep jabbing myself.
Long story short, I had a penile implant 2 months ago . The procedure was covered by my insurance. Works Awesome!!! What game changer. If you go this road make sure you use an experienced Surgeon, there are only a handful in the USA that specialize in the procedure.