These measures concern the overall size, not the size of the display...!?
The overall size confirms the image you linked to is bogus. The number of pixels and the PPI confirm the screen dimensions i.e. the narrowest dimension is identical between the 10.5 and 11.
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Regardless of pixels, comparing the two side by side in landscape, you will see more content height-wise on a webpage on the 10.5 vs. 11. Usually one or two lines of text.
Unfortunately, this can be an issue depending on how the application is adapting to the new screen. This is probably my biggest issue with the 2018 iPad Pros.