There's more to ID length concerns than just URL length. Those IDs tend to be IDs in a database which usually need to be indexed. Even packing the 128 bits of a

There's more to ID length concerns than just URL length. Those IDs tend to be IDs in a database which usually need to be indexed. Even packing the 128 bits of a UUID into a binary(16) can make your indexes quite large and make queries with joins surprisingly slow. I think extra effort to go below 64 bits may be a bit unnecessary, getting from 128 to 64 can make a big difference on the back end.