Typically when we see news using the term 0-day it's because there was no human element needed in the infection of machines. Thinking back in recent memory (17~ years) I can't remember a time when 0-day was used when it didn't mean autonomous infection.
Although. I fully understand that the term means that it's a previously unknown issue. Which is why I chose my words as carefully as I did.
The reason human intervention is generally required now is because Windows has been hardened enough that some idiot user has to click a button to bypass the built-in basic protection. There's still a possibility of a "0-day" exploit remote-owning a machine, though these sorts of exploits are a lot harder to craft due to that attack surface being exposed to more security scrutiny.