Shopstr need to implement OpenGraph's preview cards (like any webpage) for that. Also, the link is an npub, which points to a user and not an item. All things to improve :)
Discussion
It needs to Etsy like feel! People underestimate Etsy.com
Feel free to send a PR or make a bounty to get more devs involved. Otherwise, it's going to be a very long road to get Etsy on Nostr.
They are GPL: https://github.com/shopstr-eng/shopstr