Like Auldtimer,
I agree that if you can talk, you can sing - think of some of the old traditional singers, they may not have had 'good' voices but they had total belief in what they were delivering, and commitment to the song or ballad - and that is what is important! I much prefer the diamond in the rough than the polished sparkler! Imagine if someone was the only person to know a song, and couldn't /wouldn't /was discouraged from singing it - it would be lost forever!
Many years ago at summer school one of the class embers was a Canadian who had spent the previous 8 months in Ireland, heard lots of great Irish songs - but was tone deaf. He sat in our Scottish ballads and traditional singing class and did not even try to join in a chorus. At the evening sessions, he constantly asked if anyone knew. could sing, some of the Irish songs he named - but none of us came from that culture; we tried to persuade him to have a go, and eventually as the week progressed and sufficiently relaxed by whisky, he finally sang! That was the first time I ever heard Raglan Road, and it made a great impact on me - and despite his not holding the pitch etc I was able to learn the song from him - and surely that is what singing is about, communication? The guy was liberated, and for the rest of the week he sang along in class - and it didn't matter that his voice droned, the rest of us were loud enough and strong enough to support that - and how he enjoyed himself!