Customer used my product for 6 months then demanded a full refund because he "changed his mind"

I sell handmade leather goods, been in business 4 years now. Guy bought a wallet from me back in July. Full price, no complaints at purchase, left a nice review saying he loved it. Fast forward to yesterday. He emails me saying he wants a full refund because the wallet "didn't meet his expectations." I ask what's wrong with it. Is the stitching coming undone? Leather cracking? Hardware failing? Nope. He says he just "realized it's not really his style anymore" and thinks he should get his money back. I politely explained that my return policy is 30 days and that doesn't cover changing your mind half a year later after using the product daily. The wallet isn't defective. He just doesn't want it anymore. His response? "I'll be leaving a review reflecting my experience with your customer service." So now I'm sitting here trying to decide what to do. Part of me wants to just refund him to avoid the bad review. I'm a small operation and every review matters. But the other part of me knows that if I cave to this, I'm basically telling him and anyone else that they can use my products for free as long as they threaten me at the end. My policy is clearly stated on my website. The product isn't faulty. He used it for 6 months. But a 1 star review could genuinely hurt me. Been up late playing jackpot city trying to distract myself from stressing about this, keep going back and forth on what to do. For those who've dealt with this kind of thing - do you stand firm and eat the bad review, or do you just pay the extortion fee to make it go away? I genuinely don't know what the right call is here anymore.