I've had professors like that. I'm sure some of it is professors who were "educated" and built out big resumes, but are actually useless.
But the professors I know like that are a bit different. They were properly brilliant and actually did build great things, but didn't keep their knowledge up to date, especially when it comes to arbitrary standards like what range private IP addresses use.
Time comes at you fast. The brilliant engineers of years past who played major roles in developing everything we have today often seem like ordinary boomers when trying to open Microsoft Outlook. They may still be brilliant engineers, but remembering all the arbitrary standards isn't all that important.
Your example sounds to me like this. A top-of-the-line programmer doesn't need to remember the range of private IP addresses, as basic as that is. It doesn't come up enough to stick and, when it does, is easily looked up.
EDIT:
A specific example I have that really exemplifies this. My C++ professor at the University of Cincinnati was Professor Purdy. I didn't look him up beforehand. I get to class on the first day, and this dude can barely stumble through a sentence. That can be explained by his older age, but watching him use a computer was like a boomer. He'd save the same file over and over and over again so the filenames would be like Document (1) (1) (1) (1) (1).docx every time. He couldn't figure anything out.
And then he couldn't easily answer questions about C++ programming. He was confused at the most basic things.
I'm beyond confused how this guy got to where he was, so I look him up. The dude actually has a whole Wikipedia page about him and is the namesake of some advanced mathematical, computer science concept. You'd have no idea from sitting in his class.
I've had professors like that. I'm sure some of it is professors who were "educated" and built out big resumes, but are actually useless.
But the professors I know like that are a bit different. They were properly brilliant and actually did build great things, but didn't keep their knowledge up to date, especially when it comes to arbitrary standards like what range private IP addresses use.
Time comes at you fast. The brilliant engineers of years past who played major roles in developing everything we have today often seem like ordinary boomers when trying to open Microsoft Outlook. They may still be brilliant engineers, but remembering all the arbitrary standards isn't all that important.
Your example sounds to me like this. A top-of-the-line programmer doesn't need to remember the range of private IP addresses, as basic as that is. It doesn't come up enough to stick and, when it does, is easily looked up.