It wouldn't make carbon monoxide less poisonous to us, but depending on how sensitive the sensation of suffocation is made it would help us realize something is wrong and maybe even eliminate the need for carbon monoxide detectors.

Carbon monoxide isn't only dangerous because it's not oxygen, but because it disrupts our blood's normal process of absorbing oxygen and expelling carbon dioxide. My laymen understanding is that it sort of jams the door lol. As opposed to things like nitrogen which merely gets in the way but don't disrupt the process.

Imagine if instead of getting a headache and feeling sleepy when carbon monoxide was in your body you started to feel like you were holding your breath too long.