Possibly but some might respond that bombing civilian areas in WW2 was murder.
If we dismissed Salvation based on someone’s stand on current societal narratives, we’d be committing a great sin.
That is different than evaluating someone's claim of salvation based on their behavior.
I don't think that a murderer running around murdering has a claim to Christianity.
Nor do I think that a person involved in a gay marriage who steadfastly claims that that behavior is not sin, despite all historical Christian evidence to the contrary, is providing evidence of a claim to Christianity.
I would say they are not Christian based on their behavior COUPLED WITH their claims to have rejected God's evaluation of that behavior.