I think it's quite revolutionary because, until this NIP, you had to go to a particular website to ⭐ stuff. Now you can ⭐ anything, anywhere you can point to it with some sort of internet identifier, using any client that writes and signs ⭐ notes, and your star can be evaluated by anyone reading from any relay you've written your ⭐ to.

You can star Beave's Blacksmithy webpage, Beth's Baked Goods e-bay site, Vitor's Amethyst release, Michael's newest NIP, whatever.