It looks big to me, too. I wish there was something else in the photo to give us some perspective.
In 2013 I had an uncomfortably close encounter with a mama bobcat and her kits in a copse of trees near my home here in the middle of town. My English Setter weighs 60lbs and he is at least three times the size she was, so I am guessing she weighed 20lbs at the very most, likely closer to 15lbs. Maybe it’s an illusion, but the cat in the picture seems huge in comparison to the bobcat I saw.
Yes.....outside of the cropped tail, looked more like a mountain lion or something.