Simplification is indeed needed and a decent UX team could make a big impact. It will happen eventually.
On immutabilty, the Internet is already "immutable" it is just that only a handful of companies have access to it all. However, they will dredge when it is in their favor or can create drama for profit. Transparency dilutes the value of information and distributed the potential to earn from it. Currently, five or so companies own it all and use it for narrow investor gain.
Knowing everything I say is public is kind of scary. I'm probably not the only one.
Yeah, it might be scary for many, but the interesting thing is that the only thing stopping it from becoming public now, is whether Google, Facebook, Amazon etc choose not to show it. There is an illusion that it isn't public, but everything is tracked and logged. Most of what we say online is already public anyway, which is why so many Twitter users (celebrities normally) get 10 year old posts pulled up to punish them in some way. Even if they do delete them, they are not purged.