A lot have been redeemed. Especially because btc was such low value back then.
This. The most collectable things, are the things that were not meant to be collectable. The early Casascius coins weren't silver or anything else of value, and they weren't advertised as collectable. They were essentially just cheap car wash tokens that were made to represent the idea of Bitcoins as a tangible asset. If you think about numismatics, the things that are the most collectable, are things that aren't supposed to be, and the things that are least collectable, are the things that were made to be.
Ex. Old Baseball cards: Collectable because kids had them and didn't take care of them. No one thought they would be worth big money, so now they are rare the same with other old toys. They were made in huge numbers, people used them, their numbers depreciated, and now people want them.
Ex. Beanie Babies: Designed to be collectable, people hoarded them for collectors value, worthless.