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All this discussion on the appropriate crank length has been a blackpill on the average road cyclist's understanding of torque. A lot of it has been 'Z-torque' tier stuff.
Longer crank arms do result in more torque, all else being equal. Most people fretting over this ride bikes with variable gears (or the wherewithal to fit whichever ratio fits their need) though. The purpose of variable gears is to keep the torque required at the pedal within the rider's desired range. It follows that the, provided an appropriate gear is available, fitting cranks of a different length do not result in any greater or lesser power, because the rider will select a gear suitable for their power output.
The question of crank length is one of biomechanics. More optimised crank lengths may well reduce injury risks and allow for some minor gains to rider power, but by no means does a longer crank allow for more power 'for free' from the same work from the rider, nor the reverse for shorter cranks.
tl;dr pick whichever crank length is most comfortable for you, then pick your gear ratio(s) accordingly