Surprisingly, there is a Dr Jason Wright (the first search hits were an OBGYN). In his own words, there’s no reason to think it isn’t a natural object:
https://sites.psu.edu/astrowright/2017/11/22/is-1ioumuamua-an-alien-spacecraft/
https://twitter.com/astro_wright?lang=en
BTW, all, the Daily Mail’s wrong (I didn’t say lying), no surprise there, Dr. Wright doesn’t think it’s an ET craft. Also, he’s an Associate Professor, rather than a “leading astronomer”.
http://www.freerepublic.com/focus/news/3613571/posts?page=66#66