On the same page Microsoft states it from now on allows screen sizes of 6.01â€³ to 7â€³ with a fixed resolution of 1280Ã—768 pixels.
It seems to me it shouldn't matter what size or resolution the phones/tablets have. IMHO, that should be non of Microsoft's business, even if the devices run Microsoft software.
Of course, I would recommend anyone who values privacy stay away from mobile devices running ANY Microsoft software, even small seemingly-harmless games. Companies like MS seem to hate your privacy.