I just had a cursory glance at it. It seemingly allows you to “permanently” store 100MiB of data for each account you make, as well as 1GiB of modifiable cloud storage. It looks like you just need a unique email address and that allows you to make an account. If you have your own domain, you can have limitless email addresses. You can force the system to “permanently” store lots of garbage that way, for free. Public goods aren’t a right, they are an obligation. If you can force “the public” to do something for you, without any obligation for you to do something in return for “the public”, then the system is unbalanced and cannot sustain itself. “Permanent storage” means infinite duration of storage, and that it is entirely unable to ever forget anything. A system that can only ever grow, is unsustainable. Almost nothing is worth storing “forever”. It would only take a little while to grow the entire system by a terrabyte of “permanent” storage if you automate the process. Hardware costs money. Anything that the public deems unworthy of being maintained, should decay.
The idea of a permaweb is missing the point. Instead of forcing “the public” to do something, it is much healthier to give everyone the ability to voluntarily provide specific public services, such as storing/replicating specific data. And someone who contributes nothing also can’t expect to receive any services. So either you contribute valuable data which others are interested in storing, or you pay them to store it for a while. But all this is temporary. As soon as nobody is interested in storing that data anymore, and/or as soon as you stop paying anyone to store it, the data should be rightfully lost. In 100 years, nobody wants to store petabytes of garbage.