> So what if life is meaningless, why does that actually matter?

Well this is not very far from what Camus effectively landed on, the acceptance of the absurd. There's a lot that's simplified and removed from your statement, but I think you would find a lot more to agree with in Camus than you might expect. He was certainly not a nihilist or solipsist.

EDIT: To clarify, Camus thought the opposite of the grandparent comment, and was not on team suicide.