While the louvers are 'comparatively not as open' as the other 'made in Mexico BP', I don't agree with the title and WCW conclusion. What I see is plenty of openings and open enough not to make a difference, impede flow. Imo, based on the information provided him for the vid, WCW went in with a preconceived conclusion. Still many more openings in that tube than would be holes.
That said, I've had no issues with the louvers on the "made in US" Bosch Premium 3323. Also, why I make sure to include louver pic with light down tube with c&p.