Thought murtad nothing to do with race? Can still be a Malay. But no longer a Muslim.
Malay is not an ethnicity. A bugis, riau, Javanese, aceh, bawean are all Malay because their common denomination is Muslim, similar culture and language.
Malay is a societal construct with these three essential attributes. Removal of any of it removes them from being Malay.
Similarly, people from the subcontinent and china can also be a Malay upon acquiring these same three attributes.
That's why you see peranakan Cina and India are accepted as Malay and accepted as such.
The proper term of those who leave Islam is murtad. Let's call it such. Let's not sully the Malay name.