could you name some of these "possible options" back in 2008?
all i see (https://en.wikipedia.org/wiki/List_of_hash_functions#Unkeyed_cryptographic_hash_functions) is a list of a lot of hash algorithms most of which came along in recent years mostly for SHA-3.
there are old ones like MD and RIPEMD which weren't as safe or popular as SHA256
there is Whirlpool which is again not popular and the digest size is 512 bit which would have made everything in bitcoin that much bigger. so not suitable