That's bs and you know it. The after market CAI's totally eliminate the thing that would cause the most turbulence, that POS crinkly rubber hose that runs from the MAF to the TB. All the one's I pictured are totally smooth inside, might even say polished.
Air passing through restrictions makes noise. The stock airbox muffles it. Simple as that.
In any event, I change the intake when I buy a vehicle. Been doing that for over 40 years. And nothing anyone says is going to alter that. And every vehicle, including my 3.0 Ranger, runs better than they did before. It's called seat-of-the pants, and mine works.
YMMV
The stock box is EPA mandated so the vehicle can pass a noise emission test in a closed booth. Intakes are noisy. Years ago, I ran an open velocity stack on a four barrel carb. You should have heard that sucker. Man was it loud. Even idling, just one loud evil hiss. Never had any trouble with the engine either. Ran that set-up for years. It was on a Firebird with a cowl hood, and the stack stuck up into the cowl. I had a screen on the back of the cowl to keep large objects from going in. Man, I miss that set-up, the sound was beautiful to behold.
I'm gone for the day. Too nice a day to sit here inside and gab. There is no stupid stay-at-home order in effect here.