The same can be said about every performance mod ever developed since cars first appeared 100 years ago. There are mods that work, and others that don't, and the airbox mod discussed above is among the former.
Toyota does not design their airbox this way because it would make too much noise. They must compromise performance to provide an intake system that meets their noise constraints.
Rent yourself a factory stock Dodge half ton with Hemi and spend a Friday night at a local dragstrip running against guys with the same truck but with lots of simple, cheap bolt on mods. Feel free to lecture them on how "Dodge engineers would have used these mods if they actually did anything". Let us know what happens at the end of the day.