Are you sure the extruder isn’t slipping? I had some issues on my ender 3 v1 because I wasn’t extruding hot enough or slow enough, especially with certain brands. That resulted in the filament coming out way slower than expected, but some did come out. It would extrude some, skip to catch up, extrude more.

maybe the creality filaments are moist? Do you hear popping noises? if so then try drying em in a dehydrator.

I have no experience with that filament, but some of them are crap. For each filament you should find the best temp and flow. You sad you tried diferent settings, but have you done temp/flow/retraction tower calibration? You can try disabling retractions for testing, again some filaments are bad and sometimes retractions are just too frequent (compare by printing exact same model). As others said it can also be wet filament. Some filaments require diferent tension on extruder arm, but you can tell by looking at the teeth marks. At the end you want filament and settings that work best for you, I love polymaker

Is there a pattern to where the gaps are happening? Like are they always where the beginning of a layer starts printing or are they interspersed throughout layers? I recently had a similar problem with my K1 and some random filaments that were a few years old where the start/end points of my layers had holes, almost like the start of the extrusion was lagging behind the movement or the stopping of the extrusion was happening prematurely. I never really figured out the core problem because I just switched to vase mode because it worked nicely for the model I was printing. But I thought about playing with my retraction settings in case I was retracting too much or adjusting my nozzle temp in case these rolls just weren’t flowing when melted like they used to (but it sounds like you’ve tried that already). And I know it’s a bit cliche at this point but you might want to try drying your filament especially if you’re hearing pops from the nozzle when it’s printing.

I had something like this on my Ender 3 Pro, and because I had/have calibrated much of the system the retraction distance that is in the default profile was pulling in air, causing pop/bubbles in every layer after a retraction.

I dropped retraction from 6.5mm to 4mm and all the bubbles went away.

I’ve had the same issue with creality filament. I’m sticking with inland. The creality filament just sucks. It’s dry and I’ve spent far too many hours screwing around with settings. I’ve never had to fiddle with settings so much with so little return.