My 2c
Stock isn't bad at all and yes, "cold air" intakes are ineffective for that very reason. Aftermarket intakes (especially "short ram") do reduce and smooth the airflow path and increase filter area which helps with flow at high rpm, but you won't see huge gains with a stock MAF diameter intake.
Where you get real gains is moving to a larger diameter MAF housing and TIP which allows significantly more airflow. To make use of the extra flow though, you need to be tuned for much more boost than stock.
So stock vs stock+intake =not much more power; tuned vs tuned+intake =decent power; tuned vs tuned+big intake=even more power.
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