"What should a student know?" "Everything"
"What should a lab technician know?" "Almost the same as the student"
"What about a graduate?" "In which book is that thing that the student should know?"
"And the associate professor?" "Where is this book?"
"And the professor?" "Where is the associate professor?"
The higher someone is the less overall they know. I know regulars that I would put way higher than some of our experts. And its not only technical knowledge but also problem solving, attitude and craftsmanship.
Thats what happens when promotions are given based on "years worked" or "office politics" instead of work excellence.
Sad reality in a lot of companies in IT.
Promotions to new positions based on performance in the previous position don't always work out great either.
I'd suggest their skillset changes as they grow into their new role. As they transition from writing code to people wrangling, the code skills stop being important and new ones take their place. Same with attitude, they have to transition to a new focus.