And if it was always going to be uncomfortable sexual innuendos or propositioning for sex, then it wouldn't be a grey area.

The point here was incidents that don't cross "the line", which means the location of the line is suddenly up for debate, so you don't even know if you did something wrong.

Isn't the location of the line always up for debate, though? Since people created the line and give it power, it moves with our consciousness and will. The line today is not where it was in 1890. As women gain a stronger voice, we should expect the line to move. Assuming that men actually care about their input, they'd cooperate in shifting the line to an acceptable standard for both parties.

If the line is up for debate, you would know if you did something wrong - unless you're not following the debate. If you're not following the debate, you really don't have anyone to blame but yourself.

Of course, "the debate" is an abstraction and it's actually a million different debates in a million different places.