You’re right that the e2ee part is only about protecting the data while in transit, but that is because it’s the hardest part. Apps can also store the data in an encrypted format so that other apps won’t be able to read it.

Having control over the OS doesn’t help if the OS doesn’t understand the app’s data.

Provides a single process that can be used by all message apps so that they don’t need to implement backdoors into all of them?

Fun fact; Hitler is in the good place.

… It was a technicality.

Flashback:

Architect: “man this Hitler dude is so awful, whoever kills him goes to the good place, no questions asked.”

I couldn’t find any study on this.

Before and after bed usually, maybe even a third time after gym.

That link is overly exaggerating. It’s only really bad for you if you have a skin condition in the first place. Where I live showering multiple times per day is the norm and you don’t see anyone with those problems at all.