I think the word "purpose" is simply a human-made word, so it depends on us to consider if the universe has or not a purpose depending on the meaning we give to that word.
If we consider as "purpose" every change, for example: the purpose of water is to flow or to allow us to live, then the universe is the most accurate definition of "purpose".
On the other hand if we think for example "there's no point on the planets to move" and we understand "purpose" as something "useful" then, of course, the universe doesn't have any purpose.
(I'd be glad if you could correct my mistakes writing in English)
^_^