@Kye It's on Pro because people find it valuable. 🙂 We have to eat somehow. And based on my experience, it's not a required feature -- 99% of people on Write.as find the platform useful without having it at all.
WordPress.com subsidizes their free users with their sheer scale and, of course, advertising. We're working to help more people understand this, but a web that isn't subsidized by ads means that users have to start paying for the things they use.
@Kye You can always pay monthly if you prefer. Often people will actually find that they end up using the other features on Pro that they didn't imagine using at first, so you might see the same thing.
Otherwise, it's always available with WriteFreely, whether you host yourself or join another instance: https://writefreely.org/instances