@neil I don't think open follow accounts like your have the threat model of trying to prevent randos from seeing your posts. To you it would mostly add enforced encryption at rest.
For public/unlisted it would mostly add enforced encryption at rest, but follower-only posts can't be boosted. And it protects those against bad actor servers that e.g. index or publicize them.
@dequbed
I can see how it would work in the context of follower-only posts from restricted follow accounts. Absolutely.
And, just in case, I didn’t mean to be dismissive of those who choose or need to engage in that way - not at all.
In other, more public, contexts, I am less sure it would work at all!