The goal is to support the Librem 5 as well, but because the Librem 5 has a USB-C connector, it means using a hub or other adapter to use existing Librem Keys. At some point we would like to offer a USB-C connector option as well.
Also note that the Librem 5 will feature its own internal OpenPGP smartcard reader so it can already perform a lot of the security features of the Librem Key with respect to secure key storage.