The problem is not the fact aerodynamics are the main parameter, the appendices actually manage better air flow, the problem is the restriction on height of front wing that makes the profiles agressive to obtain the downforce and in consequence following car is even more sensible to turbulent air because of the height of his front wing; and the rear wing width and location aft of the rear wheels limitation that again require more agressive profile leading to turbulent air when leaving. Additionaly, rear wing are place very low to minimise drag and maximise wing/diffuser interaction wich creates an upward wash.
So, all in one the problem is how aeros are done, not how much.
Sportscar 3.5L and GTP in 92 had extreme aeros (with agressive ground effect tunnels, diffuser/rear wing interaction, front diffuser, end plates etc..) and they could follow each other easily, and guess what, they used vortex lift a lot.
There's clearly a problem to me about this lack of possibilty for following someone in a corner, but saying "too much aero" is incorrect in my opinion.