This can be observed at https://demos.telerik.com/kendo-ui/tilelayout/reordering : when you reorder the items, their "order" property changes, but their order in the HTML source stays the same. This makes the visual layout differ from the logical one.
The Sortable component, however, behaves correctly by reordering items in the HTML source.
See also: https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Grid_Layout/CSS_Grid_Layout_and_Accessibility
Hello Anna,
Indeed this seems like something which has to be revised. Currently the HTML is not reordered but rather only the visual appearance is altered.
As a token of gratitude for bringing this to our attention I have updated your account points.
Regards,
Angel Petrov
Progress Telerik