Maybe a weird design decision but it never bothers me. I don't use search a lot, but when I do I just press End on a desktop browser to immediately scroll to it, or on mobile I fling the page all the way down to the bottom. Doesn't bother me, personally.<p>I also kind of appreciate the fact it doesn't take up space above, so the search field is a little bit wider than what is normally available in other sites where it is on top.
Bottom of page never bothered me, but I wish the default sort was by date, since the relevance ranking is almost useless and I almost always want the most recent hits first.