Have followed your link to Osram, and the product data sheet.
It states very little about light output, except that the intensity is 3200 lm.
There is no data about wavelength, i.e. colour, except "Up to 20% whiter light compared to the minimum legal standard", which is almost meaningless.
If they're comparing to minimum standard for headlight output, I should jolly well hope to see an improvement over the historic standard.
Sorry, but it's a matter of physics, not marketing slogans. A light source can be brighter, for sure (= lumens), but cannot be "whiter" than something which is already white: it can only shift its spectral value, which, in this case, is a shift towards blue. The shift has nowhere else to go (except to the red/yellow)! *
* If you doubt this, try adjusting your PC monitor's white balance. You can have reddish-white, greenish-white, blue-ish white, or . . . white-white. The last is what you judge to be tint-free, "best white". You cannot improve this, only shift it to achieve a 'warm' or 'cool' white. What the headlight vendors are offering is invariably the latter (without letting it get too blue, in the case here).