Never heard of wine fridge's being too cold to keep for a long period of time. All my wine is stored at colder temps, including what I store really long term at an offsite wine storage facility.
As you mentioned, the big thing is temp variation. And this is a major reason why storing wine at "room temp" can cause issues. Also, vibration is a major factor that a lot of people don't consider. So if that central and steady temp closet is under your stairs, it can cause issues as well
As you mentioned, the big thing is temp variation. And this is a major reason why storing wine at "room temp" can cause issues. Also, vibration is a major factor that a lot of people don't consider. So if that central and steady temp closet is under your stairs, it can cause issues as well