Does it count to have a Tor mirror, while you already have a clearnet version? Because, authorities can get your server location anyways from the clearnet website. And users can always use the clearnet website with Tor.
So, what purpose does the Tor mirror serve?
Thank you for your question.

Yes the Tor mirror is exactly that, a mirror of the clearnet. Many services provide Tor mirrors.
Some people simply prefer .onion better.