Sending is depending on NIP integration by the sending App. So a zap can be sent by any lightning wallet and it will be recognised if the nostr App can do it.

But receiving is depending on the lightning address' App. Alby is not yet ready to receive zaps (and show the amount and sender on Nostr), but Alby can make tips.

NIP 57 is optional - but since now "anon" zap also possible so everyone hesitating to support it will join - many doners dnot want their handle/npub appear. payments also flows through - NIP57 show who donated publicly thats all