I understand what you're saying and think we may have different perspectives on being upfront.
It can definitely be creepy and overdone, I agree with you there. But there are also more options than the polar opposite of assuming everything is ''code''. Open and honest communication is possible without making people feel uncomfortable.
For example, testing the waters by fun flirting before outright asking someone if they want to sleep with you; not just jumping into things and assuming (that's 100x creepier)
The reason there are so many books is the problem is because men tend to overthink it. You don't need to over-analyze everything women are saying. We don't expect you to be mind-readers (except for a immature minority).
Just listen to what women say. I think there is a happy balance between being overly upfront and being nuanced. Considering I'm a woman I urge you to be thoughtful of what I'm saying.