A few questions:
> isn’t an “8-week regime for EBRT” only 40 days, not 81 days?
> How many Grays of radiation each treatment?

As for quality of life with ADT, did your oncologist recommend resistance-training exercise? My medical oncologist recommended resistance-training exercise to minimize almost all adverse sude-effects - and it worked. (The benefits of ADT far outweigh the remaining adverse side-effects.)
> https://m.youtube.com/watch?v=YE61HSAsFb0
> https://journals.lww.com/acsm-msse/fulltext/2023/04000/resistance_exercise_training_increases_muscle_mass.2.aspx

Here’s what Dr. Kwon recommends for salvage treatment of recurrence: https://youtu.be/Q2joD360_pI

(For me, at 65y quality of life was equal priority with successful treatment. My quality of life was good throughout ADT.)

I had a 40-minute drive to the radiation treatment center each day (mostly highway). Being retired, I simply worked it into my daily schedule. My wife later told me that if she hadn’t known I was undergoing radiation treatments, she wouldn’t have realized it from any change in me. And the short amount of time that I was gone each day for treatment were no different than any other time when I simply left to go shopping or to the gym.

I experienced no fatigue, moodiness, or brain fog. (I attribute that to both the enhanced resistance-training and cardio programs that I engaged in.)

After my radiation treatments were over but while I was still on hormone therapy, I asked my wife if she had noticed any emotional changes in me: moodiness, crankiness, aggressiveness, anger, etc. She said that she hadn’t noticed any. She says that except for my complaints about warm flashes, low libido, and muscle atrophy, she wouldn’t have noticed that I was getting radiation treatments or on hormone therapy.

(If I had to do the ADT again to treat high-risk disease, I would.)

Good luck with your decision.