[ormaaj]

Yes. Email on the internet is still best-effort delivery after all. If someone suspects an email somehow didn't get delivered that's a whole different situation.

Whether or not a response is expected depends on whether the respondee made their expectation clear, if it isn't implicitly clear given context. Otherwise response is at the discretion of the responder.

Like duh right? I'm remarking for the benefit of those that haven't yet had much exposure to discourse particularly among computing professionals on the internet. Expect for people to vary in their expectations, but this attitude of entitlement, expecting others to "earn" their attention is completely back-to-front. That burns people every time, and they're usually oblivious to it happening.