Interesting Point

"Research
into email has shown that email authors think that their emails are
clear, unambiguous and not subject to misinterpretation. However more
than half of the time recipients actually interpret the tone or
underlying objective of the email as being different to that intended
by the sender. It's not malicious or deliberate, it's actually
unavoidable as email does not transmit the non-verbal queues that we
usually rely on for interpretation.
Email is not a clear and objective communication mechanism."

My thanks to Mary for posting this elsewhere. I think it accounts for a lot. It doesn't explain away the name calling and dowright nasty stuff but it does explain why the spats get started in the first place, those that seem to come from nowhere. There are of course those started deliberately by trolls etc but the majority do indeed seem to start for the reasons sated above in the quote.