> All I was saying is that there's no reason to introduce more complexity into the transport layer
But there is, and I explained what that reason was. The real world is under no obligation to faithfully copy your OSI Model, on the contrary, the fact the OSI Model doesn't resemble the real world is a good reason to abandon it.
> "But there is, and I explained what that reason was."
If your reason is "security" (whatever that means, you won't define that either), then I too, explained how that is guaranteed by application-layer protocols already today - so it's unclear why changing the transport layer is needed. Again, you're not saying anything concrete and keep handwaving - I don't think you really want to (or can) have a conversation, really.
But there is, and I explained what that reason was. The real world is under no obligation to faithfully copy your OSI Model, on the contrary, the fact the OSI Model doesn't resemble the real world is a good reason to abandon it.