PLA filament no longer usable ?

One question, I have some PLA that worked perfectlt good some months ago. Since then stored in container (not airtight) with lots of small silica gel packets. Humidity below 50% RH in room. Been printing ABS an PETG, and now back to PLA.
My old PLA seems to extrude at uneven speed. If I do 200mm extrusion, it seems to run fine for 100mm or so, then a bit uneven, and finally it seems to almost stop. Then it is even difficult to push filament thru with fingers. Even at 220C. Replaced the nozzle to see if it was clogged. Pushed a metal rod back/forth in the metal tube going up from the heat block at the same time to make sure it was clean (all metal Mk8 hotend).
No difference.

Any explanations ? Has the PLA changed from perfect to variable width ? Sounds more plausible than extruder voltage too low, as pressing with fingers is almost impossible as well.

yep could simply be a bad roll.

I've never had one - but they must exist.