Why is the app "Keyguard" shown as desktop only?

on Flathub it is shown as Desktop Only

https://www.pasteboard.co/LnxwBChOJsHh.png

on Bazaar it is shown as Adaptive

https://www.pasteboard.co/IdkgrODbIm96.png

in the metainfo xml file i saw that it doesn’t have fields <required> <display_length compare="ge">360</display_length> </required>

but it does have all other fields that are in the docs that are necessary for an app to be listed as mobile and desktop

i would like to know why doesn’t flathub display keyguard as also a mobile app? what does the <required> tag do? and what would it mean for the app instead of the required tag to have a <recommends> tag?

(images not embeded cuz i dont have the perms cuz am a new user)