Default sort should be based on free software compatibility
One of the main uses of h-node is to look for compatible hardware when buying a new computer or accessory.
The easiest way to access this information is if the compatible items are listed at the top, followed by the partially compatible items, then the incompatible items.
There should still be an alphabetic sorting option, for people to be able to easily see if a particular item is compatible. But this should not be the default sort.
Sorting on freedom also helps h-node do its job of promoting freedom friendly hardware better.