Online teaching is so hard.
What is your college's policy, or yours, on whether the students must have their cameras on? At my college, we've been asked to respect the fact that some students don't have enough privacy at home to be comfortable putting their cameras on, so I don't require it. But I know that everyone having their cameras on helps with participation. However, if it's late in the semester there like it is here, I wouldn't recommend changing any policies now.
I try to get students to participate in ways that are lower risk for them. I ask "Is that making sense?" and have them give me (only me) a number 1 to 5 in chat. Even that, many of them won't do.
You described it as giving up, but I'd describe it as disengaged. I'm curious how this student is doing with assignments. I'm also wondering about his attitude. Both of his comments seem on the verge of hostile, or at least a bit disrespectful. (Maybe it depends on the tone...)
I record each zoom session, so I'd tell him it's ok to not come, and to watch the zoom later. It might be worth figuring out an empathic response to that student, and messaging him privately. "It sounds like you're feeling pretty overwhelmed. I wonder how you're feeling about this class." I guess that would depend on how he's doing with quizzes and tests. (Sadly, I have trouble with students who are cheating. As I said at the start, online teaching is so hard.)