The Mclaren Renault comparison is interesting in many ways.
Both teams had a very similar aero problem in 2018 but one team built a whole new car in 2019 while the other built the same car and grafted a superficial fake copy of the fancy raised Ferrari017 sidepods onto it.
One team increased the distance between the front wheels and the sidepods and used the raised Ferreri style sidepods to puch them beackward further to put them in a cleaner airflow, while the other team didnt puch them at all. The worst part is that every team who copied them since 2018 did that, but if you look closely Renault did not.
And that's not the only reason they look like fake and half assed copies of the Ferrari pods. If you look closely, only the first 10cm are Ferrari-like but the rest are classic sidepods with fat sides and underside...
Thats one of the 2000 reasons the aero developpement at Enstone looks excessively cautious, very timorous and often half-assed. And it seems it was a deliberate descision, remember what abisteboul said before the start of the season.
"We know that Enstone, things will take time. F1, by definition, is evolutionary and iterative, meaning that when you build a car, you take the car of the previous year and improve it on the basis of the weaknesses you could identify. on track.
This reality is that we will put a little time, a few seasons, to level the very best.
We are in a philosophy of wanting to control what we do using solutions a little conventional because we want to master things, take them step by step.
There are teams that are more radical in their choices, but we know it.
These are guidelines that can pay but can also burn your wings.
We are on an extremely constructed approach."
The aerodynamic problem Renault has might be simply inherent to the design they are using since 2018 (or even 2017) and to get rid of it they might simply have to change that design, like Mclaren did; change the turning vanes under the nose (which barely change on the Enstons cars), the T-tray and bargeboards, deflectors, sidepods etc. Abiteboul kinda aknowleged that lately.
Another typical half assed copiage by Enstone: the raised front whishbones: Every team on the grid who copied the STR-Merc raised top whishbone to clear the way underneath them has aligned the steering rod with one of the whishbones to have the cleanest possible airflow there. But Renault is the only team to retain the steering in the same place as 2018.
The siepod underside is well visible here but the pic is misleading ragrding the sidepod longitudinal position because of the different angles, proportions etc. The intakes barely change position actually.
The step by step approach has some benefits, but you're too slow Enstone, and other teams discover and learn new things faster than you.
And if your concept is flawed, you carry over the flaws in the next season.