I can totally see Facebook pushing a update which uses internal APIs to access private information outside of its sandbox.
Honestly apps need to be verified after every update for much of the same reasons they need to be verified initially. The issue is the verification process itself, which sometimes blocks legitimate developers while also sometimes allowing scam apps.
See: recent iOS exploits.
And the original poster (the blind game developer) says so too
Isn't this being possible a security issue with iOS?
You literally already have an ongoing relationship with the party in question, which is usually one of the biggest hurdles to reputation systems (new users).
I expect the real reason they haven't moved in this direction is fundamentally App Store review is seen as a tool of ongoing control rather than quality. So the more frequently something has to pass through it, the better.
If Apple can "find an issue" with your app every time you update, that's a very different relationship than an ongoing approval.
PS: Would also require developers to inform Apple of any company sale / dev team replacement to prevent abuse (Didn't mention you sold your company? Ban).
Second, Apple really hates the idea of special rules for specific developers. When they make an exception for, say, Kindle; they don't just approve Kindle. They change the App Store rules to say "apps that are just viewing content purchased on other devices don't have to use IAP". The closest thing they have to special rules are entitlements; things like Zoom's special camera multitasking entitlement comes to mind. However, even that ultimately wound up being something other developers of video chat apps could ask for, they just didn't say anything about it until they got called out on it.
The 1Password example you cite is plain 'ol trademark infringement. I imagine Apple isn't particularly interested in doing trademark enforcement for third parties, though I'm pretty sure they wrote the rules to allow them to do exactly that. This is definitely something where Apple could be more proactive, but there's a limit to how much they can do before you get people complaining about Apple going overboard.
You mean "really loves" special rules for specific developers. They won't change the public rules, of course, but backroom deals for private APIs or specific entitlements are a thing.