It might help mitigate intake air temperatures (IAT) - of which, historically, force-induction Subarus have been very sensitive to. I have never datalogged my Ascent, so that's just conjecture, but with other modern turbocharged Subarus, IAT builds quickly whenever the vehicle is stationary, and as a result, the ECU can aggressively pull timing should it sense knock conditions. My current Ascent is our 10th Subaru since 2005, and the 8th that's turbocharged - I've logged my '05 LGT extensively (which also had various intake modifications throughout her stay with me), as well as dabbled with my wife's '05 WRX and '13/'16 FXTs, and that's been a consistent observation throughout.So you took out the top piece of the grill and you cut off some of the rubber ram air tubular piece. Any difference at all of........anything. Fuel mileage, I would think if it was gonna change anything at all it would be city miles per gallon.
Historically, Subaru engineers have done such excellent jobs at intake air management that even highly respected aftermarket tuning houses like Cobb have advised against modifying the air intake system, as most "short ram intakes" ("SRI") will actually see significant increases in IAT when there's less underwood airflow.
Removing the grill(e) slat in front of the hood intake should improve airflow when the vehicle is in forward motion and thus help lower IAT faster, but I really don't know if it does or not, or even if it potentially carries implications regarding airflow dynamics further upstream, past the airbox/resonator/filter.