Honestly I had that stereotype loaded in mind myself too. I think it's probably because I've not been in a library since the days of librarians being short old computer illiterate people
All my book needs were digitised long before our local library caught up, and then of course Amazon happened
How old are you?
30 on the dot this year
For me, it's because my school librarian DID fit that description, and I never met my University librarians (everything was automated).
There was a city library near me. There may be one near you too.