NFC is a digital communications method, it is not analogue. It uses less power than BT because it is specifically for short range communication (like when you "bump" phones for payments). It uses a magnetic field similar to RFID. Communication range is in the order of cm rather than meters. There is no accurate docking required, just place it somewhere on top of the speakers. There are also no connectors to get dirty/damaged or wires to break.
Apple delay adding this kind of technology as they are extremely cautious over data security. And they will/do limit it to only audio and HID. Just like how that fancy new(ish) BMW system cannot speak text messages from an iPhone but it can from every other (modern) smart phone on the market, because Apple will not allow data transfer over BLE (Bluetooth Low Energy).