I would be surprised as well. I would assume that a colleague who called wasn't calling just to shoot the shit, so I would call them back.
A little bit in defense of Paul here, though for slightly different reasons, I had a boss that would get 100's of emails and voicemails a day. Some - his boss, his direct staff - he would answer as a matter of course. Others... if the email was vague, or poorly worded, or incomplete, he would ignore until the second prompting, on the assumption that "if it's not important enough for you to make the communication clear, it's not important enough for me to response proactively". He was senior in the organization, so there's that, but there's some wisdom to that.
If someone just calls without a VM, or sends a Teams like "Hi Bill!" with nothing else, there's only about 10 people in my organization, plus/minus, that are getting a response from me proactively.