John, it is a tough side effect - as I know personally. Andy62 on this forum is our local expert on testosterone recovery, but he pops up less frequently now. With luck he will spot your new thread, but in the meantime you might find some useful advice looking for his previous posts on the forum.
I am three years since finishing ADT with Zoladex (goserelin) as part of salvage RT; I had had a PSA upturn following surgery 6 years previously. So not quite the identical situation, but the same problem. I persuaded the hospital to measure testosterone at the same time as my last PSA test (which was <0.05) and it was 11 nmol/L The lab gives 6-27 nmol/L as their reference range, but having looked at scientific papers it is clear that 6 nmol/L is less than a healthy amount - though it indicates recovery from the drug. It seems that "normogonadic" testosterone is above 12 nmol/L, with most sexually active men having a level nearer 20. (It is a little confusing when you chase the details up, simply because the Americans and some other countries use different measurement units where normogonadic starts at 350 ng/dL).
When I had my telephone appointment with the consultant I persuaded him that things weren't right, and I got a referral to an endocrinologist who knows about testosterone. He wanted more blood tests, to include other relevant parameters, but said that if poor testosterone production is confirmed he would be prepared to prescribe testosterone supplementation. I am currently waiting for the results.
I think for a long time doctors were unwilling to give testosterone to prostate cancer patients, in case it triggered return of the cancer. However the modern view is that any stimulation of prostate cells will already have occurred with testosterone above 6 nmol/L, and supplementation above that doesn't cause any further risk. The relevant policy document is here: https://wjmh.org/DOIx.php?id=10.5534/wjmh.250086
Good luck with fighting your corner on this one, there is hope!