I tend to have some pretty good conversations with myself, so it might not be too bad 😃. I'd probably read a lot more than I do now for sure. Just to pass the time more than anything. You are right though, it would be pretty pointless. Unless aliens came along and found you or something like that.
Imagine what the aliens would think if they came and
a) you had done nothing but survive
b) you created a world of art for no one
They'd probably be really impressed or really sad I would guess :)