I've never had retention.
You said something that rings bells. 1). The anesthesia: my operations started in 1986. Prostatectomy in 1996 did include mild incontinence, but it faded slowly. But there was no big issue until three related ones in a particular hospital in Tacoma (2013), WA, then one in Anchorage, Ak, 2018. The first wiped memory from operation thru ICU thru regular hospital thru first week in nursing home. The second from the hospital lobby thru a couple of days in the ICU. Three weeks to get over the worst of the incontinence before they released me. Before those last 2 sets of operations, I always woke coherent and memory good, sooner than most, and no incontinence. My incontinence has faded to almost mild. Now you make me suspicious of the anesthesia. (as if i wasn't, already.)
There does seem to be an anecdotal link to Diabetes. You didn't say if you have that.
2) that part about peripheral nerves. My Peripheral Neuropathy (which you may not have but should at least research) started with the 2013 operations, as did the mild incontinence. Check it on Medifocus.com, or ask about it, or, at the very least, check a hospital's website to research PN. I kept track of the literature with Medifocus - they link to the latest scientific Journal studies/articles on PN. If there is a link/study on PN and Incontinence, i missed it.
That suggestion you research the anesthesia sounds like a good start.
If you get any information, please share it.