“I did not choose any of this. It was on my identity card before I could read, and the first time I said the words I was a child repeating them.”

You are describing something real, and it is worth being precise about what it is, because the precision helps.

A form recorded you as Muslim. A school taught you the words. Neither of those things is iman, and the tradition you are describing says so before any critic does. Faith requires tasdiq, the assent of the heart, and no registry has ever been able to issue that or take it away. The entry on your card is an administrative fact about the Malaysian state. Whether you believe is a different question, and it is still open, which is uncomfortable and is also the point: nobody has answered it for you, however much it may have felt that way.

So the thing you are angry about may not be the thing you think you are leaving. Being enrolled without being asked is an injury, and Islam's own position is that a compelled profession is worth nothing. If you were handed the religion as a fact about your ethnicity rather than as a claim you could examine, then something was withheld from you, and what was withheld was the choice you are only now being offered.

Take it seriously in both directions. You are free to examine this and conclude it is false. You are also free to examine it and find that you assent, which would be the first time it was ever actually yours. What you should not do is treat a decision made for you at birth as though it settles anything, in either direction.