you only stall at 1.414 times the wings level stall speed at 60 AOB IF you pull the stick back and try to hold height (ie actually pull the required g such that the vertical component of the lift vector equals the weight).
I should not have put 'try to' in this. What I said only applies if you DO hold height.
Sorry if you don't understand this.
Only if you DO hold height with 60 deg bank will you increase the lift vector to a length of double the weight (needed to keep the VERTICAL component of the lift vector equal to the weight) and so put up your stall speed to 1.414 times the wing level case.
Rolling to a high banck angle without pulling back and increasing the AOA will NOT affect the stall margin. What will happen to your flight path is another matter though.