Can anybody speak to what the issue is preventing cars from following each other closely in the turns? Loosing "clean air" and aerodynamic downforce is my completely uneducated in F1 guess.
The front wing is responsible for a lot of the downforce but loses too much of its efficiency when in turbulent air. The remedy would be moving the rear wings higher (more slipstream with the turbulent layer of air higher above the cars), simplifying the front wings (which increases drag in clean air) and making the car underbody provide more downforce. Unfortunately, that's not the direction the F1 regulations have been moving to.
[0] https://cdn-8.motorsport.com/static/img/mgl/3600000/3610000/... [1] http://www.racecar-engineering.com/wp-content/uploads/2012/1...