Well, there's the clinical data...

What you provided indicates higher risk and your medical team may not be wrong about recurrence.

The questions:

Will it return?
When?
Where?

Those are unknown other than "likely."

Other questions, age, co-morbidities, your individual preferences when balancing quality versus quantity of life.

You could be proactive and treat now based on the clinical data you have. You would need to decide in conjunction with your medical team, ADT, ARI, Radiation...if so, how long, which ADT, which ARI, what type of radiation,, do you extend the treatment to the pelvic lymph nodes, how long would you be on the ADT...would you combine two, all three, just do the ARI...?

Radiation by itself to the prostate bed with your clinical data may be "useless" given the likelihood of systemic disease outside the prostate bed.

As to the side effects, yes, this forum has the entire gauntlet and the varying degrees men have endured. Think statistics and Bell Curve, standard deviations, mean, mode, median, average.

Throughout my time on treatment over the last 10+ years I have not had the side effects interfere with living with the exception radiation places on traveling.

Mitigating the side effects can in part be a function of:
Diet
Exercise
Managing stress.

I've peaked behind the door of death by, not with prostate cancer. It's a hard no for me and my medical team knows that and in part, it is a factor in our decisions.

So, talk with your medical team, discuss what criteria they and you think would necessitate a decision to treat, then, through labs, imaging and consults, actively monitor your PCa, treat when those criteria are met and inform the treatment decision.

Another thing to think about and discuss with your medical team is what is the risk of actively monitoring and not treating until that decision criteria is met?

You have choices, that's the good news. It's also the uncertainty since there is no definitive answer, it depends. Guidelines such as the NCCN and AUA are based on science but are population based and lag behind ongoing medical research.

Kevin