Oh man…welcome to the most difficult decision you will ever have to make - with no backsies!
First of all there are no wrong decisions - outcomes for survival are the same. Both treatments have side effects so basically, pick your poison - as distasteful as that sounds.
At age 70 surgery is certainly a viable option but you better be sure you select an excellent surgeon - open surgery in these times seems a bit medieval but I am not a surgeon so perhaps there are reasons - but THAT is very invasive and a longer recovery than a robotic procedure.
OTOH, there are many options with radiation and not all of them take months - some just about 2 weeks.
However, with G8 you’d probably be placed on ADT for 6-12 months - longer if your RO feels the need.
I know I probably have not helped you much but after living in this PCa world for over 6 yrs (surgery and then SRT with ADT) I’ve come to realize that even though ALL OF IT sucks you do manage to get through whatever brilliant decision you think you’ve made; and once you’ve made it, embrace it, put your blinders on and charge forward…NEVER, EVER look back!! Best,
Phil