We obviously have a difficulty in that different pilots believe the "max demonstrated cross wind component" figure has been obtained in different ways. Without the manufacturer telling us how the tests were carried out we can only speculate.
My personal view is that for large transport aircraft, the figure is obtained as suggested by FF above, i.e. the aircraft is landed with crab and no attempt is made to align the u/c prior to touchdown because this will give reproducible results. I don't agree, however, that the u/c will fail at the max demonstrated figure, there will be a safety margin, but the lateral forces might well be at the design limit for the u/c. This can be easily confirmed by strain guages on the u/c during certification.
The lateral strength of the u/c is only one possible limiting factor. An aircraft with stronger undercarriage could lift a wheel (or bogie) or otherwise lose directional control beyond a certain cross-wind component.
So unless the manufacturer tells us how the figure was arrived at, we can only speculate. However, unless the figure is quoted as a limit, it isn't a limit, and some aircraft don't have any figure quoted at all.
Don't get me started on inaccurate reporting of surface wind at some airfields !