This is what I’ve seen most often in my career. Problem is, the contact is almost always the admin. I’m the admin. Everyone’s idea of assistance is different. Often, I didn’t have the knowledge about the issue in order to be of any assistance. I wound up spending more time running around looking for answers than actually working on what was on my own plate. It’s exhausting. Otherwise known as “please don’t call us for unicorn problems when we handle llamas. Literally, we can’t do anything for unicorn problems.”
I had a colleague who simply never answered her phone or set up her voicemail. She still listed the number on her business card and email .sig, she just never answered or checked voicemail. When she took a new job another colleague inherited her phone number and when he went to set up his voicemail there were basically eight years’ worth of messages left for her that he had to delete.

I once emailed someone I barely knew to check on some materials he was supposed to send my boss and I received an auto-reply letting the world know that he was away in Vegas with his “boyz” to celebrate his divorce. I still don’t know why he felt this was important to share with business contacts. “I’m away for the week” was all the information I needed.
About the “overshares”: You linked to a previous column that mentioned this point, “Sometimes the over-sharing of plans can even come across as suspect — similar to how when someone’s calling in sick with genuine illness, they usually just say, ‘I’m going to be out sick,’ but fakers will generally give you a long list of overly specific symptoms, like they feel they have to convince you.”