How long do you have filament sitting “in the open”? I mostly print with a single filament roll at a time, and just leave it on the printer. A 1kg roll lasts me several weeks. For long time storage I keep it in an air tight box with disiccant pouches.
But how long can I let it sit before I should start storing it with disiccant and/or drying the filament before use?
I’ve literally never had my filament not just sitting on the spool on my printer, which is just kept on my desk in my living room. Never had any problems with it.