The stock creality extruders are pretty trash. They have a tendency to not grip the filament well enough, or alternatively, grind the shit out of it leading to slippage.

My first upgrade on those machines is always a dual gear extruder. There should be a drop-in replacement for <$20 on Amazon. They're almost always coated in red paint, should make it easy to find :p

It’s a pretty trashy extruder.

I’d highly recommend the micro Swiss dual gear

I upgraded to a Creality Sprite Pro direct drive unit and it has been a game changer in terms of quality and consistency. Best thing I’ve done.

As others have said, it's not a great extruder, but I've never heard of any "crushing" the filament. Perhaps you could post some photos of the filament and the extruder? Despite its flaws, it should still be usable (unless the plastic tension arm has started to break).

The tension adjustment on that extruder isn't the greatest and the best fix in the long run would be upgrading it to a better design. But in the mean time, I find there's sometimes a bit of slop in the extruder mounting to the stepper. If you loosen the screws that secure the extruder to the stepper you may be able to move the extruder assembly in a way that gives the filament more space between the gear mounted to the stepper shaft and the pinching gear on the extruder arm. Yymv, sometimes theres a bit of play and sometimes theres not but it could help.

Are you sure it isn't brittle filament from being left out and getting "damp".

I am guessing you are talking about PLA here?

First, I don't think it's the extruder crushing it, I think your filament is brittle.

Whenever you bend PLA (e.g. unroll it from the spool, or even worse, run it through the bowden tube, it develops microcracks.

In the space of a few days, these cracks make the filament super brittle.

Before loading the filament, take the loose end of the filament and bend it a bit. If it breaks like spaghetti, that part is brittle due to these cracks. Keep going until you reach a part that you can bend by almost 90° without it snapping. Break/cut it off at that point and load only the non-brittle part of the filament.