Your hope is in conflict with reality.

That is the expectation but no way to enforce it of course.

What happens a lot, at least for me, is that people will start reading the comments to see if they want to bother reading the link. Then they might start commenting on what's already been said. It's easy to slip into that pattern.

Though you also frequently see top-level comments that appear to be based on the headline alone.

I have some bad news for you...