Well, yes an no. I don't like statements from my medical team that are "all or none" choices. It indicates to me that they are not current in their practice or worse, biased based on their clinical speciality.

There are some who advocate for removing the prostate in this situation - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5449684/ while combining systemic therapy such as ADT or chemotherapy and potentially whole pelvic lymph node radiation with boosts and wider margins around the identified sites. The idea behind removing the prostate is to eliminate the mother ship though with he PLNs identified, maybe not. Yes, the surgery has side effects, well known. Those will vary based on in part the skill of the surgeon, whether or not it is nerve sparing....I had mine in March 2014, no incontinence, nerve sparing, I was able to and still have the ability to gain and maintain erections though with assistance, daily Cialis and greater stimulation required. Yes, the ejaculation is gone, some miss it others don't. Sex is different after surgery, no doubt, but for those who are fortunate to have nerve sparing surgery, there is a vast array of possibilities in penile rehab therapy. A couple can also choose to "redefine" sex other than just penetrative intercourse.

There is also the option to not remove the prostate and do doublet or triplet therapy combining radiation and systemic therapy to eradicate the PCa cells in all identified locations as well as the micro-metastatic disease too small to be seen by even the most sensitive imaging today - https://www.mdanderson.org/newsroom/metastasis-directed-radiation-therapy-plus-hormone-therapy-improves-progression-free-survival-for-men-with-advanced-prostate-cancer.h00-159543690.html#:~:text=Metastasis%2Ddirected%20therapy%20(MDT),which%20is%20continuous%20hormone%20therapy.

So, he has options, try and do some literature searches on the options, have discussions with your medical team (urologist, radiologist, oncologist) and with their input, decide what is best for you two.

Kevin