Interestingly, as layers and layers and layers have been added, the basic concept of a “port” – “input / output” has become a strange, convoluted thing, which really isn’t that hard, but it’s made to be purposely hard. Keeps people employed.
They’ve gone from being “ports” into being “communications protocols”.
Why? Well, if they didn’t, I’d be able to type on your screen right now… which would be damned cool. [by the way, I can do that. I’m doing it right now]