People can and do claim whatever identity they want.
Certainly in liberal secular societies you can do that. And whilst calling yourself a *insert religion here* atheist may raise some eyebrows, you can still do it, because you are free to call yourself a dolphin worshipping Jewish Hindu agnostic pantheist if you so desire. That is what free conscience is all about.
The problem is, with Islam, how it is received by Muslims themselves, and by Islam institutionally, whether there is a space for such a description with any kind of resonance or credibility under the umbrella of Islam.
"we can smell traitors and country haters"
God is Love.
Love is Blind. Stevie Wonder is blind. Therefore, Stevie Wonder is God.