This is like the gif where everyone draws a picture on the back of the person in front and the end result is nothing like the original. Chinese whispers in art form!
You can almost hear the not-quite-accurate descriptions that inspired these. Like the (many) images that are almost accurate, except the tusks grow upward: probably the description called them "horns" and mentioned where on the head they grew from, but not the direction, so the artists simply inferred the horn-growth direction they were familiar with from other large mammals.