You could. But it’s not a direct replacement for the home pod. The speaker is similar to an Alexa speaker and is always on and waiting for you to say, “Hey Siri” or just “Siri”. The Apple TV does not have an always on mic. You’d have to use the remote and press it down. To be fair, I’m not sure if the remote is always listening. I assume not, I’ll check in a bit b

If using the remote only to toggle Siri options is enough then yes you could use it as a sort of replacement.