Denmark checking in. A lot of our highways have separate parallel bicycle highways. It's really great! They have exits in the same spots as cars do and have big sound barriers.x

anywhere that you might say "we shouldn't have a bike lane here, it's too dangerous for cyclists" is a place where there should be a bike lane.

If you only have a hammer ...

Well it’s a good thing no one is proposing that! Seriously, where do you people come from?

You're looking at what is obviously a conceptual diagram and acting as if it's some kind of literal blueprint. IMO it's something closer to a Sankey diagram showing the overall flow and moda share of traffic into the city than a plan sketch of an individual road. I don't think it's even reasonable to conclude that it's actually suggesting using the same alignment for cars, bikes, and pedestrians at all, let alone strawmanning it as "a bike lane on a highway."

Frankly, I'm found it to be a tough call deciding whether you genuinely didn't understand that or if you were commenting in bad faith (which violates rule 1), and the only thing that made me give you the benefit of the doubt was your later comment talking about the cement barrier (i.e. a somewhat constructive comment about how to make it better) instead of continuing to flatly reject it.