The DMA does not define such details, it is much more simple and agnostic. It identifies if a company creates a market within its own ecosystem, invites others to participate but doesn't offer a fair competitive field.

--> If iOS introduces non-standard changes to Bluetooth and Wi-Fi to compete against Android, this does not concern the DMA.

--> If iOS introduces non-standard changes to Bluetooth and Wi-Fi to create a product of ANOTHER market-segment (Headphones, Watches, Routers,...) they are required to provide interoperability for other brands than Apple as well.

The reason is simple: iOS has such a critical size that it is anti-competitive behavior for Apple to modify iOS in order to beat the competition on e.g. headphones.

With Bluetooth they do ruse non standard changes, heavily influenced the development of LE Audio and there is no statement about when if ever they will support LE Audio, possibly never. Apple simply doesn't care