[antonchekhov]

I don't understand why, if the recipient of the initial detached "hello" is annoyed at the communication tax of having to acknowledge it before the querier gets to the real point of the convo, why in the "preferred" example, he/she responds to their gratitude ("ta") with a "np"? That seems like just as much pointless communication noise, only at the other end of the chat. When I say thanks to anyone in real-life verbal communication, their (usually a grunt) "no problem" adds nothing.

[sceptic123]

It's mostly about flow, you are already interrupted by the hello, and may have to wait some time before their response to your reply (as they then have to type out their actual question.

Thanks/No problem is closing off the interruption so there's no future expectation.

[eddd-ddde]

It's not about trying to eliminate social interaction, it's about minimizing asynchronous overhead and unnecessary waiting.

That last "np" is a little nicety that lets the other person know their question was happily answered, no waiting created.