I used you.com before and they have the search bar on the bottom, this is super helpful on mobile where you want to quickly amend or change the search text.
most browsers changed the url bar to the bottom for the same reason, now I change the search in the url bar since that is easier, but then I loose the suggestions of the kagi search.
I would like to have it as an option, the UI already has so many options adding the option to move the search to the bottom on mobile (and desktop) is a great way to improve the UX on phones