And I've used such services, yes. But this looks way too minimalistic to me to be useful.
On Patreon I subscribe to a specific artist. I know who they are and they can know me if we talk to each other. I can favorite posts, provide feedback, get perks, etc. When an artist says that for $10 I'll get access to their latest sketches that's a public announcement on Patreon, and if they don't hold up their promise, fans will get upset.
Here there's an obscure link. I don't know what I'm paying for, or who made it. I don't know whether it belongs to the actual person who's supposed to benefit. Somebody could pay for the first access, make their own link and then leech off the actual artist by spreading their link around.