The picture I linked is of a buckwheat pillow. Had no idea they were a thing before today.
What about silk or bamboo pillow cases?
I've only ever really used cotton pillow cases and cotton stuffed pillows. I recently upgraded to a foam pillow that I'm enjoying.
Eh, I've tried all of them at least once.
For my money, shredded memory foam is the best. It isn't perfect, but I've had the best balance between comfort, durability, ease of cleaning, and cost.
Buckwheat was good at support, and stayed fairly cool, but the breakdown and difficulty of cleaning made it a problem. It just doesn't last as well. Only thing that was worse in that regard was feathers. Feathers get ruined faster than anything else I tried.
Pillow cases, I'm a cotton fan. High thread count cotton has the right balance of softness vs smoothness. Too soft, and you end up with bunching and wrinkles as you move. Too smooth, and you end up with your head moving too easy but your hair not moving well.
Polyfill sucks for everything except ease of cleaning.
Cotton batting is about the same as polyfill, but not as easy to clean.
Solid foam is just begging to sweat heavy, and damn near impossible to clean well. Plus the durability is iffy.
Pillow cases, actual linen isn't bad, but tends not to be as comfy as cotton. Silk is way too smooth. Satin is just uncomfortable. Synthetics tend to run hot, even though they feel nice. Knit cotton feels the best, but damn does it fall into poor condition fast.
Really all of them? Camel fur? Natural latex? Lyocell? Sheep wool? Pinus cembra shreds? Horse hair? Kapok?
All I want to say is: there is a whole world of relatively unknown pillow stuffings available. This is mostly useful for people with very particular requirements or allergies.
I tried all the regular ones (cotton, different grains, down feathers) plus camel fur, latex and Kapok. Latex was great, durability was mediocre compared to the price though. Kapok became flat pretty fast.
I arrived at the same conclusions as you did: shredded foam. I'd go with natural latex, which has about the same properties and can be manufactured in an eco-friendly, sustainable fashion, but that led to me spending $120 on a pillow that didn't last a third as long as a foam pillow for $22.
Edit: I'm also biased because I want my pillow to be washable. That helps with all kinds of allergies, plus the dirt you see coming out of the pillow... Jesus.
Yeah, latex is by far the best. True, it's expensive but definitely worth it! I've had mine for two years now I think and it's great, no issues whatsoever.