The most frustrating thing to me is to receive a 5-paragraph-plus email that was clearly written with some AI that filled in the email with vapid and useless talking points, like "Let me know if you need any other blah blah blah; While there is clearly a need for system improvement, we are working hard to address the underlying and fundamental issue; This is a lesson that it's not just a feature, it's a critical path for our users, etc."

My theory is that people are fundamentally averse to the thought and effort it takes to write a good quality email. Then there’s probably some underlying belief that more volume shows more effort, which people will perceive positively. And finally, there's the worry that if you write the email yourself, you might make some embarrassing wording, grammar, or spelling mistake.