Just another datapoint to muddy the waters:
In the beforetime, I was commuting to work daily, about 50 minutes total (split over 2 rides to/from) at moderate intensity. No stretching. Nightly leg cramps were frequent.
During lockdown, I've been riding 5-6 times a week at higher intensity, at least an hour at a time. I stretch for a few minutes afterwards most days but not all. I've had one nightly leg cramp in the past 2+ months.
I have a thimble of scotch before bed maybe half the time. My drinking has gone down a little during lockdown. But I've seen no correlation between my level of alcohol intake and nightly leg cramps. I may not be drinking enough to register.