You would think a website dedicated to talking about software engineering would agree with this sentiment wholeheartedly.
A zero day generally means a vulnerability and associated exploit have been identified and the vendor didn’t yet provide a patch. It doesn’t just mean “there is a vulnerability”. To say that every software has vulnerabilities is just not a useful comment
The difference between
"We found aliens!"
And
"Aliens are out there!"
It's a zero day that has been released to the public with full exploit code.