There is the Alby Account with the lightning address, the Alby Extension - those do NOT give you a node. You have to connect a node to those. NWC (Nostr Wallet Connect) is the best spec for that.

Alby Hub comes with a lightning node.

So Alby Hub is the node/wallet/where your sats are and you connect other services (Extension, Account, Nostr Clients, etc.) to that one.

does this explain it?